chore: drop remaining context module legacy refs

Follow-up sweep after acb737e25 — the context module's UI + Dexie
tables + AI route were already removed, but a handful of registry-style
refs in the monorepo's plumbing still pointed at the dead module:

- packages/shared-utils/src/analytics.ts: drop the `context: createModuleTracker('context')`
  entry from the `track` map and delete the unused `ContextEvents`
  helper (no consumers — every analytics call site that used it lived
  in the deleted module).
- packages/shared-utils/src/analytics.ts (cont.): the deletion above
  removes the only typed reference to track.context, so the property
  cleanly disappears from the inferred type.
- package.json: drop 6 dead npm scripts (`context:dev`, `dev:context:web`,
  `dev:context:app`, `dev:context:full`, `dev:context:local`, `setup:db:context`)
  — all referenced `@context/*` workspace packages that were removed
  with the module. `pnpm context:dev` would silently succeed-with-zero-targets
  before; now it correctly errors as unknown script.
- scripts/generate-env.mjs: drop the two `apps/context/apps/{server,web}/.env`
  generator entries pointing at non-existent app directories.
- scripts/validate-monorepo.mjs: drop `'@context/'` from the internal
  workspace prefix list — fences a class of dependency that no longer
  exists.
- .env.development: fix a stale comment pointing at the renamed
  /api/v1/context/import-url endpoint (now /api/v1/kontext/import-url
  per acb737e25).
- apps/context/: delete the leftover directory (CLAUDE.md describing
  vanished paths + a package.json with a `dev:mobile` script filtering
  the @context/mobile package that was deleted with all per-product
  mobile apps on 2026-04-20).

What remains and is intentional: historical plan docs / devlogs /
audit reports / generated complexity-map.html / Dexie v57 drop
migration / pnpm-lock.yaml (regenerates on next `pnpm install`).
Unrelated `'context'` strings (MemoryCategory enum, Kontext-Agent
template id, encryption-vaults DB column, Astro landing /context
content collection) stay — different concepts that happen to share
the word.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

scripts/validate-monorepo.mjs

@@ -145,7 +145,6 @@ function checkWorkspaceProtocol(packagePath, packageJson) {
 		'@mana-games/',
 		'@figgos/',
 		'@worldream/',
-		'@context/',
 	];
 
 	for (const [depName, depVersion] of Object.entries(deps)) {