APP-4344: Add first-party Oz lifecycle hooks

[warp-agent-staging]

Description

Implements the approved APP-4344 first-party Oz lifecycle-hook contract behind OzLifecycleHooks.

• Adds strict user/project config discovery and composition, exact-byte SHA-256 trust, deterministic matching, and protected-path handling.
• Adds typed, bounded, redacted payloads for all seven v1 events and a FIFO subprocess runtime with allowlisted environment, timeouts, cancellation, output bounds, and deny-only parsing.
• Wires local and AgentDriver session, prompt, tool, compact, and terminal lifecycle behavior without changing third-party harness-native hooks.
• Negotiates and handles MAA RunOzHook actions using the pinned warp-proto-apis contract.
• Restores local conversations with SessionStart { source: resume } before inference and publishes failed/blocked terminal status only after exactly one matching Stop completes.

Linked Issue

• APP-4344
• Implementation follows the approved specs/APP-4344/PRODUCT.md and specs/APP-4344/TECH.md contract.
• No UI changes; screenshots and video are not applicable.

Testing

• cargo test -p warp oz_hooks_runtime --no-fail-fast — 10 passed.

• Focused resume, shared stop-claim, failed-stop ordering, and blocked-stop ordering tests — all passed.

• ./script/format — passed.

• cargo clippy -p warp --all-targets --tests -- -D warnings — passed.

• CARGO_INCREMENTAL=0 ./script/presubmit — format, inline-test policy, workspace Clippy, clang-format, factory-files checks, and WGSL formatting passed. The workspace nextest phase was blocked only by the unrelated Linux X11 recording test records_window_target_via_native_x11grab_after_raise, which cannot foreground/capture its target in this sandbox and fails independently when rerun.

• I have manually tested my changes locally with ./script/run (not run: this is non-UI runtime behavior and computer-use verification was explicitly excluded).

Agent Mode

• Warp Agent Mode - This PR was created via Warp's AI Agent Mode

CHANGELOG-OZ: Added first-party Oz lifecycle hooks for session, prompt, tool, compaction, and stop events.

[warp-agent-staging]

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