fix(advance): add ctx threshold check before /breathe

[birdmanmandbir]

Summary

• Ports shouldBreathe logic from the deleted cmd/task_route.go into internal/daemon/advance.go
• Adds pure shouldBreatheStatus (unit-testable) and thin shouldBreathe I/O wrapper
• Guards the /breathe send in advanceToStage — agents below breathe_threshold (default 40%) are skipped
• Stale (>5min) or missing status files default to true (breathe when uncertain)
• Adds TestShouldBreatheStatus to breathe_routing_test.go covering nil, stale, below/at/above threshold cases

Test plan

• go test ./internal/daemon/... -run TestShouldBreatheStatus -v passes
• make test passes
• Agent at 0% ctx: ttal task go skips /breathe, logs "skipping breathe for X (ctx below 40% threshold)"
• Agent at >40% ctx: ttal task go sends /breathe as before
• No status file: defaults to sending /breathe (safe fallback)

[birdmanmandbir]

PR Review — fix(advance): ctx threshold check before /breathe

Critical Issues

None.

Important Issues

None.

Suggestions

internal/daemon/advance.go:390 — route file staged but no notification when breathe is skipped

When shouldBreathe returns false, the route file is already staged (line 375) but no signal is sent to the agent. The agent only learns about a new route when it restarts via /breathe. If the agent is idle with ctx near 0% (e.g. just started, no active loop), the route will accumulate silently until the next natural breathe cycle.

This is probably acceptable by design — an agent with very low ctx is likely still in an active work cycle and will be breathed again shortly. But worth confirming: is there a fallback notification path, or is the assumption that ctx < threshold always implies an actively running agent?

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Strengths

• Clean pure/impure split — shouldBreatheStatus is pure logic (fully unit-testable), shouldBreathe wraps I/O. Excellent engineering.
• Safe defaults — nil status, stale status (>5min), and read errors all default to true (breathe). Fail-safe direction is correct.
• Boundary condition tested — at threshold case (ctx == threshold → breathe) is covered explicitly.
• All 6 edge cases covered in TestShouldBreatheStatus: nil, stale, below, at, above threshold, and zero ctx.
• Informative skip log — includes agent name and threshold value, making it easy to trace in production.
• >= for threshold — semantically correct (threshold means "breathe at this level or above").

VERDICT: LGTM

Solid fix. The pure function extraction and test coverage are particularly well done.

[birdmanmandbir]

Triage Update

VERDICT: LGTM — merging

Suggestion Addressed (by design)

Route file staged but no notification when breathe is skipped — this is intentional. An agent below the ctx threshold is assumed to be in an active work loop and will encounter its next natural /breathe cycle (context usage grows, eventually crosses threshold). The route file is consumed at that point. The safe-default behavior (stale/nil → breathe) ensures a dormant agent doesn't silently accumulate routes indefinitely.