ci: skip cache/revalidate.test on the http lane (subprocess-only)

The result cache's conditional revalidation (304 / not_modified) is
subprocess-only by design: the if_none_match validator rides the first
producer tick, but over HTTP that first exchange folds into the /init
POST before any tick is sent, so the not_modified path never fires and
the worker is re-invoked. revalidate.test asserts a revalidation HIT
(stable nonce), which then fails over HTTP.

The test deliberately omits `require httpfs` so it auto-skips under a
plain HTTP harness, but this CI lane force-injects `LOAD httpfs` before
each ATTACH, defeating that auto-skip and running the test over HTTP.
Add it to the http-lane EXTRA_SKIP alongside the other known-HTTP
limitations. The launch/stdio/shm lanes still run it.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: rustyconover

ci/run-integration.sh

@@ -73,11 +73,18 @@ if [ "$TRANSPORT" = "http" ]; then
   #   * buffer_input/sizes.test — input buffering semantics differ over HTTP
   #     (same known limitation). (scale.test_slow is a .test_slow file and is
   #     never staged below, which only finds *.test.)
+  #   * cache/revalidate.test — conditional revalidation (304) is subprocess-only:
+  #     the if_none_match validator rides the first producer tick, but over HTTP
+  #     that first exchange folds into the /init POST before any tick, so the
+  #     not_modified path can't fire (documented in the test header + vgi CLAUDE.md).
+  #     The test omits `require httpfs` to auto-skip under a plain HTTP harness, but
+  #     this lane force-injects `LOAD httpfs`, defeating that — so drop it explicitly.
   EXTRA_SKIP=(
     -not -name 'projection_pushdown_repro.test'
     -not -name 'dynamic_filter.test'
     -not -name 'partitioned_sequence.test'
     -not -path './table_in_out/buffer_input/sizes.test'
+    -not -name 'revalidate.test'
   )
 fi