* feat(lambda): add SAM template and sample events for AWS deployment
Phase 6.2 of the distributed rendering plan (DISTRIBUTED-RENDERING-PLAN.md
§15). Reference SAM template for deploying HyperFrames distributed
rendering on AWS — one Lambda function in three roles, choreographed by
a Step Functions standard workflow with a Map state for parallel chunk
rendering.
Resources created by the template:
- Lambda function pointing at the Phase 6.1 ZIP
- Step Functions state machine: Plan -> Map(N) RenderChunk -> Assemble
- S3 bucket for plan tarballs, chunk outputs, final mp4
- IAM role for the state machine
- CloudWatch alarm guarding against runaway chunk invocations
Retry policy: 4 attempts, 2s initial, 2x backoff, max 60s, with the
typed non-retryable error codes from plan §9.3 explicitly opted out.
CodeUri points at packages/aws-lambda/dist/handler.zip; sam deploy
resolves the local path and uploads to a SAM-managed bucket on first
deploy.
Validated: sam validate --lint passes against the template.
This is part of the 8-PR Phase 6 stack; PR 6.2 of 8.
* fix(lambda): address PR 879 review feedback
- Add CloudWatch alarms for Lambda Errors metric (5min window, threshold 1)
and Step Functions ExecutionsFailed metric. The existing runaway-
invocations alarm catches too-many-calls but missed silent per-chunk
failures and retry-exhaustion.
- Document VersioningConfiguration: Suspended tradeoff inline. Adopters
treating the final mp4 as user-keepable should bump to Enabled.
- Cost-allocation Tags on RenderBucket + Lambda Globals.
- Lambda Tracing: Active so X-Ray spans don't terminate at the SF→Lambda
boundary (the state machine already had tracing).
- State-machine top-level TimeoutSeconds: 3600 as defensive ceiling on
the whole choreography — catches Plan-retry storms before they hit
individual task budgets.
- AssertChunkCount Choice state: if Plan ever returns ChunkCount=0 the
Map would silently iterate zero times and Assemble would receive an
empty ChunkS3Uris[] producing an empty output. Fail-fast with typed
PLAN_TOO_LARGE error instead.
- Architecture comment: explicit x86_64-only constraint from
@sparticuz/chromium so adopters trying Graviton don't get bitten.
* docs(lambda): drop internal plan-doc refs from SAM example + template
James Russo