fix(auth): watch identity instead of one-shot read

[ba1uev]

getUserId returned Unknown when the host's identity lookup hadn't resolved yet, leaving the badge stuck on "??" for the whole session. The host did a single read on login, so a cold network read that returned null was never retried.

Now it subscribes via watchIdentity and updates state once the username resolves. The e2e test waits for the badge to resolve before running.

[github-actions]

⚡ Performance Report

⚠️ No baseline found on main. This PR's results are recorded but cannot be compared.
Merge to main to establish a baseline.

[github-actions]

Bundle Size Report

Chunks over 500 KB:

File	Raw	Brotli	Gzip
host/assets/paseo.smol-DboPaEh1.json	1.84 MB	941.7 KB	1019.4 KB
host/assets/paseo-people-next.smol.json	3.36 MB	1.68 MB	1.82 MB
host/assets/previewnet.smol.json	886.0 KB	121.6 KB	162.8 KB
host/assets/smoldot_worker.js	2.92 MB	2.19 MB	2.20 MB
Total	10.44 MB (-284 B)	5.39 MB (-449 B) (-48%)	5.73 MB (-694 B)

All files

File	Raw	Brotli	Gzip
host/.well-known/apple-app-site-association	738 B	738 B	738 B
host/.well-known/assetlinks.json	986 B	986 B	986 B
host/assets/auth.js	462.6 KB (+105 B)	175.6 KB (+104 B)	221.5 KB (+26 B)
host/assets/blake2.js	10.1 KB	3.2 KB (+18 B)	3.7 KB
host/assets/bridge.js	5.4 KB	1.8 KB (+2 B)	2.1 KB
host/assets/browser.js	22.9 KB	7.6 KB	8.6 KB
host/assets/client.js	93.0 KB	27.4 KB (+32 B)	30.1 KB
host/assets/container.js	53.9 KB	13.2 KB (+20 B)	14.8 KB (+1 B)
host/assets/dist.js	20.6 KB (-4.3 KB)	4.8 KB (-2.9 KB)	5.4 KB (-3.2 KB)
host/assets/dist.js	28.8 KB (+3.9 KB)	10.0 KB (+2.2 KB)	11.1 KB (+2.5 KB)
host/assets/dist.js	24.9 KB	7.7 KB	8.6 KB
host/assets/dotli-debug-bus.js	495 B	495 B	495 B
host/assets/index.css	47.8 KB	7.4 KB	8.3 KB
host/assets/index.js	106.5 KB	29.0 KB (-2 B)	34.0 KB (+5 B)
host/assets/log.js	972 B	972 B	972 B
host/assets/manifest.js	22.6 KB	7.3 KB	8.0 KB (+1 B)
host/assets/mode.js	1.7 KB	600 B	664 B
host/assets/nanoevents.js	215 B	215 B	215 B
host/assets/nova-scale.js	6.7 KB	2.6 KB	2.9 KB
host/assets/panel.js	84.9 KB	23.1 KB (+4 B)	26.3 KB (-1 B)
host/assets/paseo.smol-DboPaEh1.json	1.84 MB	941.7 KB	1019.4 KB
host/assets/paseo-people-next.smol.json	3.36 MB	1.68 MB	1.82 MB
host/assets/paseo.smol.json	142.2 KB	23.0 KB	32.1 KB
host/assets/previewnet.smol.json	886.0 KB	121.6 KB	162.8 KB
host/assets/resolve.js	152 B	152 B	152 B
host/assets/rolldown-runtime.js	694 B	694 B	694 B
host/assets/rpc-resolve.js	2.5 KB	1.0 KB (-3 B)	1.2 KB (+1 B)
host/assets/shared-mode.js	1.9 KB	793 B (-1 B)	896 B (-2 B)
host/assets/smoldot_worker.js	2.92 MB	2.19 MB	2.20 MB
host/assets/spans.js	1.6 KB	765 B	914 B
host/assets/src.js	1.9 KB	891 B (+2 B)	1000 B (+2 B)
host/assets/styles.css	15.1 KB	3.2 KB	3.8 KB
host/assets/substrate-client.js	7.2 KB	2.7 KB	3.0 KB
host/assets/ws.js	25.8 KB	8.4 KB	9.1 KB (+1 B)
host/dotli.png	11.5 KB	11.5 KB	11.5 KB
host/favicon.svg	1.8 KB	1.8 KB	1.8 KB
host/host-sw.js	2.8 KB	1.1 KB (+14 B)	1.3 KB (+2 B)
host/icon-192.png	12.5 KB	12.5 KB	12.5 KB
host/icon-512.png	42.8 KB	42.8 KB	42.8 KB
host/index.html	20.2 KB	4.5 KB (-5 B)	5.5 KB (+2 B)
host/manifest.webmanifest	441 B	441 B	441 B
host/workbox.js	14.8 KB	4.6 KB	5.1 KB
sandbox/app-sw.js	8.7 KB	2.8 KB (+3 B)	3.2 KB (-4 B)
sandbox/assets/bitswap-bridge.js	840 B	840 B	840 B
sandbox/assets/fetch.js	3.4 KB	1.2 KB	1.4 KB (-1 B)
sandbox/assets/index.js	118.1 KB	33.7 KB (+27 B)	39.6 KB
sandbox/assets/index.css	47.8 KB	7.4 KB	8.3 KB
sandbox/favicon.svg	1.8 KB	1.8 KB	1.8 KB
sandbox/index.html	1.7 KB	582 B (-2 B)	786 B
Total	10.44 MB (-284 B)	5.39 MB (-449 B) (-48%)	5.73 MB (-694 B)

_{Commit: 60a0383}

[github-actions]

❌ E2E Product suite failed on 8780f49af31898b5a2399ebbbca9bbb673babfc1 — 41 passed, 4 failed, 17 skipped.

Failed tests:

• Submit
• In-App
• Factory
• Submit

Logs: https://github.com/paritytech/dotli-community/actions/runs/27683100357
Artifacts: e2e-product-results (uploaded above) — open the failed test's trace.zip with npx playwright show-trace.