fix: resolve runtime/setup issues in six 01-features samples

[rhbelson]

Summary

Six 01-features/ samples had code-level issues that prevented them from running cleanly. Each fix is applied and the touched file is gate-clean (ruff check + ruff format --check under the repo-root config, py_compile clean). Complements #1998 (CI-clean doc/CLI fixes) and #1999 (docstring + arity fixes) — no file overlap.

Fixes

#	File	Problem	Fix
1	02-host/.../03-strands-openai/agent.py	Hardcoded <YOUR_API_KEY>/<YOUR_API_BASE>/<YOUR_API_VERSION> → opaque Azure auth failure	Read from env (AZURE_API_KEY/AZURE_API_BASE/AZURE_API_VERSION); fail fast with a clear message if unset
2	04-manage-context/memory/00-getting-started/04-quickstart-boto3.py	Hardcoded QuickstartMemory → ValidationException on re-run	Timestamp suffix QuickstartMemory_{int(time.time()) % 100000} (underscore per the [a-zA-Z][a-zA-Z0-9_]{0,47} regex)
3	06-observe/.../01-observe/data_protection.py	data-identifier/PhoneNumber is not a valid managed identifier → policy fails	Corrected to PhoneNumber-US in both the audit and de-identify statements
4	05-auth/.../04-outbound-auth-self-hosted/self_hosted_agent_oauth.py	Required manual create_cognito.sh run + copy 6 env vars; script path not resolved relative to itself	Auto-run create_cognito.sh (resolved relative to __file__), parse its exported values, inject into the environment when the OAuth vars are unset; --create-cognito still works
5	07-centralize/.../gatewaylabproject/scripts/waf/deploy.py	associate_web_acl fails with WAFUnavailableEntityException (gateway eventual consistency)	Retry loop (up to 6× with 10s backoff) around the associate call, catching that specific exception
6	04-manage-context/memory/00-getting-started/05-quickstart-agentcore-sdk.py	Required MEMORY_EXECUTION_ROLE_ARN set manually; hardcoded name fails on re-run	Auto-create the execution role if missing (mirrors the boto3 quickstart) + unique memory name per run

Lint cleanup (no behavior change)

Each touched file also carried pre-existing whole-file ruff debt that the python-lint gate lints on any change. Cleaned it: import sort (I001), explicit check=False on a pre-existing subprocess.run that already handles returncode (PLW1510), and # noqa on intentional demo-style broad-except handlers (BLE001/S110) — consistent with the repo's tutorial-code philosophy (root config already relaxes E722).

Testing

• python3 -m py_compile clean on all six files.
• uvx ruff@0.16.4 check --config pyproject.toml → All checks passed; ruff@0.16.4 format --check → 6 files already formatted (repo-root config, as CI uses).
• Note on verification fidelity: fixes are source-verified + gate-verified here (not each live-deployed in this session). Fixes 1 (env-var fail-fast) and 4 (auto-cognito) are the highest-confidence structurally; 5 (WAF retry) and 6 (auto-role) exercise runtime branches worth a live confirmation before merge if desired.