fix: enable strict mode, honest HTTP boundary, and add routing

Three fixes to the parts of the template that contradicted its own
"illegal states unrepresentable" claim:

- tsconfig: turn on strict + strictTemplates (measured zero fallout —
  the codebase already typechecked cleanly, it just wasn't enforced).
- RemoteData<T> drops its unused error type parameter (Resource.error
  is always Error) and Failure now carries a real Error. Pages read the
  union with @let instead of re-deriving from the resource, which
  deletes the non-null assertion strictNullChecks would otherwise flag.
- users.adapter.ts never checked response.ok, so an HTTP error resolved
  as a garbage Success and crashed instead of reaching RemoteData's
  Failure branch. New shared/infrastructure/http.ts adds the status
  check plus hand-written parse guards and abortSignal forwarding; the
  six fetch stubs across the test suite (which encoded the missing
  check) and adapter spec now cover the Failure and Empty paths.

Also adds real routing (@angular/router was a dependency with zero
imports and a fake "Back" button): /users and /users/:id are now
deep-linkable via withComponentInputBinding(), tested with
RouterTestingHarness driving real navigation.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>

tsconfig.app.json

@@ -5,10 +5,6 @@
   "compilerOptions": {
     "types": []
   },
-  "include": [
-    "src/**/*.ts"
-  ],
-  "exclude": [
-    "src/**/*.spec.ts"
-  ]
+  "include": ["src/**/*.ts"],
+  "exclude": ["src/**/*.spec.ts"]
 }