feat(aws): Kinesis Video Streams + signaling channels

[NitinKumar004]

Summary

Adds the Amazon Kinesis Video Streams control-plane service (kinesisvideo) — video streams and signaling channels — as a new greenfield restJson1 handler. Track-1 control-plane only: no GetMedia/PutMedia data plane, no real video. This is distinct from the existing kinesis (Data Streams) service, which is not modified.

Full 3-layer build: services/kinesisvideo/driver/, providers/aws/kinesisvideo/ (COW memstore mock, Snapshottable), server/aws/kinesisvideo/ (wire handler), wired into providers/aws/aws.go and server/aws/aws.go, coverage docs regenerated.

Operations

• Streams: CreateStream, DescribeStream, UpdateStream, UpdateDataRetention, DeleteStream, ListStreams, TagStream, UntagStream, ListTagsForStream
• Signaling channels: CreateSignalingChannel, DescribeSignalingChannel, UpdateSignalingChannel, DeleteSignalingChannel, ListSignalingChannels
• Resource tagging: TagResource, UntagResource, ListTagsForResource

Computed-field stability (drift-free)

Streams/channels are created directly ACTIVE (waiters never hang). The StreamARN — arn:aws:kinesisvideo:<region>:<acct>:stream/<name>/<creation-unix> — the Version token, Status and CreationTime are minted once and stored. UpdateStream / UpdateDataRetention / UpdateSignalingChannel rotate the Version token; every other computed field stays stable across reads, matching real Kinesis Video.

Dispatch

POST-to-action-path (POST /createStream, /describeStream, /createSignalingChannel, …), registered before the S3 catch-all. The stream/channel paths are unique. The three resource-level tagging paths (/TagResource, /UntagResource, /ListTagsForResource) are also claimed by Savings Plans, so this handler scopes them to a request body carrying a :kinesisvideo: ARN and registers before Savings Plans; a non-Kinesis-Video ARN falls through. restJson1 errors carry exact exception names (ResourceNotFoundException 404, ResourceInUseException 409, InvalidArgumentException/InvalidResourceFormatException 400) with X-Amzn-Errortype.

Terraform live e2e (aws_kinesis_video_stream, real hashicorp/aws)

• apply (name + data_retention_in_hours + media_type + device_name + tags) → created, status ACTIVE, no hang
• plan -detailed-exitcode → exit 0, no drift on arn/id/creation_time/version
• update device_name + tags → in-place apply, Version bumps (8d4c3522… → 25243932…), subsequent plan clean (exit 0)
• destroy → DescribeStream returns ResourceNotFoundException (404)

SDK dependency aws-sdk-go-v2/service/kinesisvideo is test-only; the lean-binary no-engine-deps test stays green.

Deferred (control-plane scope)

Data plane (GetMedia/PutMedia/GetDataEndpoint), media storage configuration, and signaling edge config are out of scope for Track-1.