Svelte + TypeScript: fail loudly on companion TS timeouts; deterministic test fixture

Make the Svelte companion TypeScript server raise on readiness and
indexing timeouts instead of silently proceeding with a partial index,
turning flaky/wrong cross-file results into clear failures:

- TypeScriptLanguageServer: timeout handling factored into overridable
  hooks (_handle_server_ready_timeout, _handle_project_indexing_timeout);
  the base server keeps its historical permissive behavior, so plain
  TypeScript setups are unchanged.
- SvelteTypeScriptServer: both overrides raise TimeoutError; only the
  indexing-timeout error includes describe_indexing_state(), instead of
  serving requests from a cold or partially indexed program.
- Configurable server_ready_timeout / indexing_timeout via
  ls_specific_settings.
- SvelteLanguageServer: file-open failures during companion preparation
  raise SvelteCompanionPreparationError with a count-first file listing
  (capped at 10), chained to the first underlying error so the cause is
  visible without DEBUG logging.

Apply the same fail-loudly principle to the test fixture bootstrap:

- Svelte test repo: npm ci with a committed package-lock.json, removing
  dependency-resolution non-determinism from CI runs.
- Run svelte-kit sync explicitly during fixture setup and fail loudly if
  .svelte-kit/tsconfig.json cannot be generated. The fixture's "prepare"
  script masks sync failures ("svelte-kit sync || echo ''"), and a known
  npm bug (npm/cli#4828) can silently skip platform-specific optional
  dependencies; the result is unresolvable $lib path aliases and
  cross-file tests failing with partial results instead of a clear,
  actionable error.
- codespell: skip third-party fixture repositories, using the anchored
  pattern ./test/resources/repos (codespell matches skip globs against
  the ./-prefixed paths it walks, so an anchor-less pattern never
  matches).

Also add direct regression tests for the timeout-policy split
(test/solidlsp/test_typescript_timeout_policy.py: base stays
permissive, companion raises, settings plumbing and precedence, and
start-or-completion indexing-wait semantics). The tests use no mocking or
patching of any kind; a hand-written call-recording fake drives the companion
guard against real file discovery under a pytest tmp_path. They spawn no LS
process and avoid external readiness races; one wait test uses a real Timer
with a 30s ceiling.

The configuration docs state that the TypeScript table lists both knobs; the
Svelte table lists indexing_timeout, with readiness inheritance documented in
prose.

test/resources/repos/svelte/test_repo/.gitignore

@@ -23,6 +23,5 @@ vite.config.js.timestamp-*
 vite.config.ts.timestamp-*
 
 # Lock files
-package-lock.json
 pnpm-lock.yaml
-yarn.lock
+yarn.lock