Improve subscriber stream error logging

[casey-brooks]

Summary

• Adds subscriber stream log context for Subscribe/Recv/rooms refresh phases, service target addresses, room snapshot counts/samples/fingerprints, gRPC code/description, and retry backoff.
• Suppresses repeated identical subscriber stream errors while logging the first full occurrence and periodic summaries with suppressed counts.
• Improves closely related runnerdial and zitimanager retry/error logs with service/identity/backoff/auth context.
• Adds unit coverage for room snapshot formatting and repeated stream error suppression.

Closes #205

Test & Lint Summary

• go test -json ./... | tee /tmp/agents-orchestrator-test.json >/dev/null: 151 passed / 0 failed / 0 skipped.
• go test ./...: passed.
• go build ./...: passed.
• go vet ./...: passed with no errors.

[casey-brooks]

Test & Lint Summary

• go test -json ./... | tee /tmp/agents-orchestrator-test.json >/dev/null: 151 passed / 0 failed / 0 skipped.
• go test ./...: passed.
• go build ./...: passed.
• go vet ./...: passed with no errors.

[casey-brooks]

Completion Summary

• Implemented subscriber stream log context for Subscribe/Recv/rooms refresh phases with service target addresses, room snapshot counts/samples/fingerprints, gRPC code/description, and retry backoff.
• Added suppression for repeated identical subscriber stream errors while keeping the first occurrence visible and emitting periodic summaries with suppressed counts.
• Improved closely related runner dial and Ziti manager retry/error logs with actionable service/identity/backoff/auth context.
• Added unit coverage for snapshot formatting and repeated-error limiter behavior.

Test & Lint Summary

• go test -json ./... | tee /tmp/agents-orchestrator-test.json >/dev/null: 151 passed / 0 failed / 0 skipped.
• go test ./...: passed.
• go build ./...: passed.
• go vet ./...: passed with no errors.

[casey-brooks]

Validation Update

• Rechecked PR Improve subscriber stream error logging #206 for issue Improve subscriber stream error logs with identity/service/agent context (Unauthenticated: identity not available) #205 after rebasing against origin/main; branch is current.
• Confirmed subscriber logging includes phase, service/target, room snapshot counts/fingerprint/sample, gRPC code/description, backoff, and repeated-error suppression summaries.
• Confirmed closely related runner dial and Ziti manager logs include added service/identity/backoff/auth context.

Test & Lint Summary

• go test -json ./... | tee /tmp/agents-orchestrator-test.json >/dev/null: 151 passed / 0 failed / 0 skipped.
• go test ./...: passed.
• go build ./...: passed.
• go vet ./...: passed with no errors.

[rowan-stein]

Requesting review.\n\nFix for #205: subscriber logs now include operation phase + target address + room snapshot fingerprint/counts/sample + grpc code/desc + backoff, with suppression/summary for repeated identical stream errors (including the "Unauthenticated: identity not available" case). Also improved a few closely related low-context logs and added unit tests.

[noa-lucent]

Review complete. The subscriber stream logs now include the required phase, service target, room counts/sample/fingerprint, gRPC code/description, and backoff context; repeated identical stream errors are rate-limited with summary logging. The closely related runner/Ziti retry logs also have clearer context, and the new formatting/rate-limit helpers have unit coverage.\n\nI attempted to run go test ./... locally, but this checkout cannot resolve generated .gen packages and the environment lacks gcc for cgo, so local verification could not complete here.