refactor(metadata-protocol): move getDiscovery's body into its facet, and settle the card's last facade-gate rows (#31177)

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Fixes #30147

Clause-②: no
Metadata-protocol: none

## 维护者速读

- 改了什么:把 `getDiscovery` 的方法体从 `protocol.ts` 搬进所在分区的
facet(`ProtocolDiscoveryAndBasesFacet`),类上只留签名和一行委托;并按裁决 6687801899 收尾
facade 门禁登记表里这张卡名下剩下的行。
- 为什么改:这是本卡最后一个 PR。`getDiscovery` 靠 `typeof this.searchAll ===
'function'` 决定是否对外宣告"支持搜索",codemod 的 host 转发会让这个判断恒为真,所以手工搬:类上读实例自己的
`searchAll` 再交给 facet 判断。
- 风险与回滚:纯搬移,方法体除搜索探针改读参数外不变(撤销证明可逐字节重建中间态 X);公开 `index.d.ts` /
`index.d.cts` 与 main 逐字节相同;回滚即 revert 本 PR。
- 先看:`packages/metadata-protocol/src/protocol.ts` 中 `getDiscovery` 的存根(传
`this.searchAll` 那一行);`protocol-discovery-and-bases.ts` 中 facet 的
`search: typeof searchAllOnInstance ===
'function'`;`scripts/facade-delegation-registry.json` 的 8 处改动。
- 两分钟验证:`pnpm check:facade-delegation-only`,预期末行 `5 facade class(es) in
3 file(s) hold delegations only, 15 named exception(s).`,退出码 0。
- 需要你做的:无,席位落地。

## What changes

**`getDiscovery`, a hand move in three commits.** The codemod's members
pass
refuses this member on `main`: its body reads the instance method
`searchAll`
as a value to set `capabilities.search`, and a host entry forwards a
method
through a closure that is always a function, so a moved probe would
advertise
search on every host. The route the card records (dev report 6686885545,
`phase_3b`):

1. `43df6766ff` is the intermediate X: the probe reads a parameter,
`searchAllOnInstance`, instead of `this.searchAll`. Not a landing state
on
   its own (the public signature carries the parameter there).
2. `4a2e27e428` is `node scripts/codemod-split-protocol.mjs --members
getDiscovery --write`
run on X, unedited: the body goes to `ProtocolDiscoveryAndBasesFacet` by
the E1 form (460 body lines), and the stub forwards `protocolHost(this)`
   and the parameter.
3. `e87a512b0e` is the hand edit: `getDiscovery()` takes no parameter
again,
so its signature is `main`'s byte for byte, and the stub hands the facet
   `this.searchAll`, read on the instance. The facet keeps
   `typeof searchAllOnInstance === 'function'`. The stub also gains a
   two-line comment that says why.

`host-split.mjs`'s refusal of a method read as a value is unchanged.

**The registry** (`scripts/facade-delegation-registry.json`), per ruling
6687801899:

- the `getDiscovery` row is deleted (16 to 15 exceptions, on `main`
after #31151);
- `triggerAutomation`, sql-driver `get supports` and
`static DIALECT_CONNECT_TIMEOUT` keep `card: "#30147"` (the gate
requires a
  card number) and each reason is prefixed with
  `accepted terminal exception (ruling 6687801899):`, the reason already
  written kept after it;
- the four `engine.ts` rows (`homeAmountServing`,
  `projectHomeAmountsOntoPatch`, `ScopedContext#derive`,
  `[APP_AUTHORED_HOOK_API]`) point at #30975.

`engine.ts` and `sql-driver.ts` are not touched.

**A patch changeset** for `@objectstack/metadata-protocol`: the
package's
built JavaScript changes (the body now runs from the facet module) while
its
public `.d.ts` does not, and `Metadata-protocol: none` takes `patch`.

## Tests

No test file changes. Measured on the final head `56dbba9841` (this
branch
merged with `main` `56baf78e0c`; the merge touched neither package):

- `@objectstack/metadata-protocol` vitest: 321 files passed, 4 skipped;
  22,525 tests passed, 26 skipped. `typecheck` exit 0, `build` exit 0.
- `packages/rest` vitest (it loads `@objectstack/metadata-protocol`
through the built `dist/`, rebuilt from this head): 398 files, 7,782
tests
passed, 354 skipped. `discovery-search-capability-agreement.test.ts`
4/4.
- The same two suites on `e87a512b0e` (before the merge) gave the same
counts.
- **Negative control**: the stub handed a host-style forwarding closure
instead of `this.searchAll`; the package rebuilt and the closure
confirmed
in `dist/index.js` and `dist/index.cjs` (`ablation-dist-preflight.mjs`);
`discovery-search-capability-agreement.test.ts` failed 2 of 4 ("agrees
on a
  protocol that cannot search" and the anti-vacuity case). Restored from
  `HEAD` (blob hash equal, `git diff HEAD` empty), rebuilt, the closure
  absent from `dist/`: 4/4 again.

## Acceptance notes

- **The `.d.ts` bar.** `dist/index.d.ts` and `dist/index.d.cts` built
from
`main` `af3451b08b`'s two source files and from this branch's are
byte-equal
(sha256 `1b94b057e16e19b5…` on all four). `getDiscovery` is public with
a
written return type and no docblock, so nothing moved out of the printed
  declaration.
- **Reproducing the generated commit.** `git checkout 4a2e27e` and
`node scripts/codemod-split-protocol.mjs --members --verify --base
43df676`
  exits 0. On the head the same command exits 1, naming exactly the
  hand-edited stub and signature (expected; that is the third commit).
- **`triggerAutomation`'s reason** now reads "accepted terminal
exception
(ruling 6687801899): accepted exception (#30147 phase 3): …": the order
was
  to prefix and keep the reason already written, and that reason already
  opened with its own label. A one-word tidy is the seat's call.
- No open pull request touches
`packages/metadata-protocol/src/protocol*.ts`
or the registry that this branch could collide with; #30747 (engine.ts)
is
  untouched here.

## Verification

<details><summary>Suites on the final head</summary>

One locked run at `56dbba9841`: `pnpm --filter
@objectstack/metadata-protocol build` exit 0, `typecheck` exit 0, `exec
vitest run --maxWorkers=2` exit 0 (Test Files 321 passed, 4 skipped;
Tests 22,525 passed, 26 skipped); `pnpm --filter @objectstack/rest exec
vitest run --maxWorkers=2` exit 0 (Test Files 398 passed; Tests 7,782
passed, 354 skipped); `discovery-search-capability-agreement.test.ts`
verbose: 4 passed (the ordinary host, a host that does not mount the
route, a protocol that cannot search, anti-vacuity).
</details>

<details><summary>Undo proof against X</summary>

`node scripts/codemod-split-protocol.mjs --members --verify --base
43df676` on the tree of `4a2e27e428`: exit 0.

```text
undo proof (#30518, #30147): 1 moved member(s) (getDiscovery); forms: e1 1; host-split check: 1/1 E1 move(s) pass (the receiver forms move bodies unedited, proved byte-equal); protocol.ts 12606 -> 12147 lines; undoing the moves does rebuild the base protocol.ts, protocol-host.ts and section modules byte-for-byte once the 15 import binding(s) only moved bodies read are pruned from the base (ApiRoutes, CHANNEL_SURFACE_SLOTS, CORE_SERVICE_PROVIDER, CapabilityDescriptor, SERVICE_CONFIG, ServiceInfo, WellKnownCapabilities, engineCanRollBack, isSubscribableChannel, readAuthFamilies, readChannelRoute, readServiceSelfInfo, resolveDiscoveryEnvironment, resolveDiscoveryVersion, serviceUnavailableMessage)
```
</details>

<details><summary>Facade gate</summary>

`pnpm check:facade-delegation-only` at `1a84657c25`: exit 0, `5 facade
class(es) in 3 file(s) hold delegations only, 15 named exception(s).`
</details>

<details><summary>dispatch-gates</summary>

`node scripts/pm/dispatch-gates.mjs --commands --repo
objectstack-ai/objectstack` at `56dbba9841`: 65 families derived, all 65
run after a full `pnpm build` (plus a rebuild of the packages the `main`
merge touched), every one `exit 0`, codes captured before any pipe.
`--ran`: 65 derived, 65 run, 0 NOT-MEASURED (a derived zero: all 65
recorded an exit code), 0 UNRUN. `pnpm --filter @objectstack/spec
check:generated`: all 14 artifacts up to date (a first run reported
`check:test-typecheck` as `tsc failed without diagnostics` on a
contended box; the gate alone and the re-run both pass). eslint on the
two changed source files: exit 0.
</details>

<details><summary>Changed lines</summary>

1,033 changed lines (+554 / -479, 4 files, changeset included), under
the 3,000 budget.
</details>

Session: https://claude.ai/code/session_017ihL2ebbZkr2QAEG1x7UC8

🤖 Generated with [Claude Code](https://claude.com/claude-code)

<!-- signed: domain:devx#2 · marchtian ·
session_017ihL2ebbZkr2QAEG1x7UC8 -->

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: objectstack-fleet[bot]

.changeset/30147-get-discovery-facet.md

@@ -0,0 +1,11 @@
+---
+'@objectstack/metadata-protocol': patch
+---
+
+refactor(metadata-protocol): `getDiscovery` hands its body to its facet
+
+Clause-②: no
+Metadata-protocol: none
+
+- `ObjectStackProtocolImplementation#getDiscovery` keeps its signature and return type on the class and delegates in one line to `ProtocolDiscoveryAndBasesFacet.getDiscovery`, which holds the body, moved unchanged except for the search probe: the class reads `this.searchAll` on the instance and hands it in, so `capabilities.search` still answers whether this protocol instance serves search. No behaviour changes and nothing to do on upgrade.
+- The published `index.d.ts` and `index.d.cts` carry the same public surface.