fix(bridge): unify active ensure and reconnect recovery (Layer 1b)

[jackwener]

Summary

Layer 1b for Browser Bridge stability, stacked on #2031.

This rewrites the earlier readiness-only patch into a full active ensure path:

• extracts low-level browser config (src/browser/config.ts) so runtime.ts and daemon-client.ts share timeout constants without a runtime/browser import cycle
• moves daemon HTTP/status/shutdown transport into src/browser/daemon-transport.ts, preserving the fix(browser): enforce fixed daemon bridge port #2031 fixed-port + OPENCLI_DAEMON_PORT fatal guard
• adds waitForBridgeReady + pre-dispatch error classification in src/browser/bridge-readiness.ts
• moves BrowserBridge._ensureDaemon() logic into ensureBrowserBridgeReady() in daemon-lifecycle.ts
• makes sendCommandRaw() use the full ensure path for pre-dispatch daemon errors and local TypeError before resending with a fresh transport id
• keeps command_result_unknown and client-side AbortError non-retryable
• rewrites extension reconnect to phased fast/slow retry without the old give-up cliff
• uses production-safe Chrome alarm cadence (0.5 minutes) and reschedules pending slow timers to fast cadence after /ping succeeds
• raises default OPENCLI_BROWSER_CONNECT_TIMEOUT from 30s to 45s so the CLI has margin over Chrome's 30s alarm wake floor

Verification

• HOME=$(mktemp -d) npx vitest run --project unit src/browser/bridge-readiness.test.ts src/browser/daemon-client.test.ts src/browser.test.ts src/cli.test.ts
• npx vitest run --project extension extension/src/background.test.ts
• npx vitest run --project extension extension/src/
• npm run typecheck
• npm run build
• cd extension && npm run build
• HOME=$(mktemp -d) npm test -> 527 files / 5542 passed / 1 skipped
• OPENCLI_DAEMON_PORT=19999 node dist/src/main.js daemon status -> clean actionable error, exit 78
• OPENCLI_DAEMON_PORT=19999 node dist/src/daemon.js -> clean actionable error, exit 2

Note: cd extension && npm run typecheck currently fails in this checkout because the extension package does not have its own installed @types/chrome; root typecheck, extension build, and extension vitest pass.