feat(ui): Steps for servers — route roots, server effects, request/decorator triggers, guards for Python/Java/Kotlin/C#/Go/C

- api/route-roots.ts: the symbol a route runs (references-edge handler, exported page component, or the route itself for an inline handler), shared by steps and screens; the bare Steps tab lists an API's endpoints by router file
- api/effects.ts: database / response / queue / email / payments / cache / auth / process / network / storage / device / telemetry, matched on the call as written per language family, with model + read/write and the literal status on a response site
- graph/branch-guards.ts: callSitesForFile (the whole member chain), memberTypesInTree, decoratorsForFile, request/decorator triggers with the middleware/guard chain; guard + argument rules for Python, Java, Kotlin, C#, Go and C
- steps.ts: classify on the chain before trusting a name match, retarget this.x.y() by declared type, skip test doubles after the effect pre-check, project kind on the wire
- viewer: kindWord/kindWords per project kind, endpoint chooser, response boxes labelled by status codes
- python.ts: FastAPI detected from a monorepo sub-directory; is-test-file: samples/examples package paths are not tests
- tests: ui-steps-api-servers, ui-effects, branch-guards-languages; spec §3.13 Servers paragraph, CHANGELOG, plan doc

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01REFyW9hmNrxhwN5wxRoAkC

__tests__/branch-guards.test.ts

@@ -203,8 +203,8 @@ func f() {
 
 describe('branch guards: unsupported', () => {
   it('reports no guards for a language without rules', async () => {
-    expect(supportsBranchGuards('python')).toBe(false);
-    expect(await guardsInSource('def f():\n  if x:\n    go()\n', 'python', 3, 4)).toEqual([]);
+    expect(supportsBranchGuards('ruby')).toBe(false);
+    expect(await guardsInSource('def f\n  if x\n    go()\n  end\nend\n', 'ruby', 3, 4)).toEqual([]);
   });
 });