mcp: every wait on the MCP path gets a bound, and a failed reload keeps what it had ...

reload_tools kept dying on prod, and only a restart cured it. Nothing on the
MCP path was bounded: ClientSession was built without read_timeout_seconds, so
the SDK waited forever (anyio.fail_after(None)); _send awaited a future with no
timeout; disconnect() awaited the shielded runner with no timeout; and
disconnect_all() walks the pool one client at a time, so a single wedged client
blocked every reload that came after it. A cancelled caller only cancelled
itself — the runner stayed wedged, which is why it was every reload, not one.

Bounds, in two deliberate layers. The SDK read timeout ends a request nobody
answers *inside* the runner, so the client stays usable; the caller-side bound
is the backstop for an op queued behind a stuck one, and it aborts the runner
rather than leaving it for the next command to queue behind. connect 60s,
list_tools 45s, call_tool 300s (SDK 240s), session read 30s, disconnect 15s,
each overridable, each logging the culprit.

disconnect() and disconnect_all() no longer swallow CancelledError — that is
exactly how the reload budget stopped being enforceable.

The registry is now rebuilt in one step: collect every server's tools first,
then commit the whole set in a single synchronous swap. clear_external_tools()
ran *before* the rebuild, so a rebuild that failed halfway left the model
holding MCP tool names that resolved to nothing. A failed pass now leaves the
previous registrations untouched, and the reload phase carries its own budget
so the tool always returns a report.

Two more defects fell out of the audit. The streamable_http transport was
handed a bare httpx.AsyncClient, whose 5s default read killed the GET stream of
an idle server — six of the nine prod servers are streamable_http. And
register_mcp_tools called log.warning() in a module where log was never
defined, a NameError on precisely the failure path it was meant to report.

Add auth resilience: user cache, retry, and API token fallback ...

- 30-second in-memory _user_cache to avoid hammering gnexus-auth
- _fetch_user_with_retry: one retry after 1.5s sleep on transient failure
- API token fallback when OAuth cookie is present but refresh fails
- Clear cache/locks in test fixture to prevent cross-test pollution
- Fix registry timeout test after lowering default to 90s

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Make Settings immutable (frozen=True) and fix all test mutations ...

- Add frozen=True to SettingsConfigDict in navi/config.py
- Convert model_validator to mode="before" since mode="after" cannot mutate frozen instances
- Replace all field-level monkeypatches in tests with whole-Settings object replacement
- Ensure cross-module settings consistency (content_store, session_files, share_file, content_publish, filesystem)

392 passed, 1 skipped

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Fix ollama_backends / FallbackOllamaBackend issues ...

- registry.py: always use FallbackOllamaBackend (unified backend).
  Enables model priority lists in all deployments, not just multi-server.
- agent.py: add missing think=profile.think_enabled to run() (REST endpoint).
- compressor.py: fix model param type (str → list[str] | str | None).
- fallback.py: harden load_servers_from_file against missing/bad JSON files
  and entries without host. Add clear_blacklists() for manual reset.
- admin.py: add POST /admin/ollama/clear-blacklists endpoint.
- tech_debt_review: document dead stream() methods.
- tests: add tests for single-server fallback, bad file handling,
  missing host skipping, and blacklist clearing.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Add regression tests for content publishing and LLM timeouts

Add context provider registry all accessor

Bootstrap test suite — Phase 1 unit tests ...

- docs/testing.md: testing strategy, mock strategy, phase breakdown
- tests/conftest.py: autouse fixture to reset navi.config.settings per test
- tests/conftest_factory.py: FakeLLMBackend, FakeTool, make_profile, make_registry helpers
- tests/unit/core/test_events.py: wire serialization for all 15 event dataclasses
- tests/unit/core/test_compressor.py: should_compress, partition_messages, format_for_summary, compress_context
- tests/unit/core/test_registry.py: ToolRegistry, ProfileRegistry, BackendRegistry
- tests/unit/core/test_context_builder.py: system prompt caching, persona injection, goal anchor, iteration budget
- tests/unit/profiles/test_base.py: Pydantic model coercion, defaults, extra fields
- navi/core/context_builder.py: use module-level `import navi.config` instead of `from navi.config import settings` so tests can swap the singleton

59 tests passing.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>