2.x gap: restore ingest OpenCode stream and hook parity

[willwashburn]

From the Rust 2.x gap catalog.

Current 2.x status:

• burn ingest supports one-shot scan, --watch, --interval, and --hook claude.

Missing/different from 1.x parity:

• --opencode-stream
• --opencode-url
• --opencode-global
• daemon diagnostics
• default/watch --quiet parity
• Claude hook mode validates payload shape but performs a full sweep rather than the 1.x single-transcript fast path.

Acceptance:

• Restore OpenCode stream ingest flags and behavior or document an intentional replacement.
• Restore quiet/diagnostic behavior expected by automation.
• Add a single-transcript Claude hook fast path if parity is still desired.
• Add tests for watch/stream/hook behavior that can run deterministically in CI.