Ability to submit Flink statements in snapshot mode.

[James Robinson (jlrobins)]

Summary

Adds support for submitting Flink statements in bounded "snapshot" (batch) mode instead of the
default continuous "streaming" mode, via the CCloud REST API's sql.snapshot.mode: "now"
statement property.

• New FlinkSnapshotMode enum (BATCH / STREAMING) and a FlinkStatement.mode getter that
  reads the mode back off a statement's spec.properties (New property mode in FlinkStatement #1849)
• submitFlinkStatement() accepts an optional snapshotMode and sets sql.snapshot.mode: "now"
  on the request when submitting in batch mode (Accept FlinkSnapshotMode optarg when submitting new flink statements #1850)
• New CodeLens toggle ("Mode: Streaming" / "Mode: Snapshot") on Flink SQL documents, backed by a
  new toggleSnapshotModeForUriCommand and a UriMetadataKeys.FLINK_SNAPSHOT_MODE metadata key,
  following the existing compute-pool/database CodeLens pattern (New codelens widget for toggling between batch vs streaming mode (?) #1853)
• The chosen mode is per-document, persists like the other CodeLens settings (compute pool,
  catalog/database), and defaults to streaming when unset; "Clear Settings" resets it too
• Added snapshot_mode to the existing Flink statement submission telemetry

Part of the batch-mode-queries epic (#1848). Follow-up work — surfacing the mode in the
statement tooltip (#1851) and the results viewer (#1852) — is intentionally out of scope here
and will land in a separate PR; the results viewer works unmodified for snapshot-mode statements
today.

While Here

• .vscode/launch.json: added --disable-extension confluentinc.vscode-confluent to the "Run
  Extension" debug config so the marketplace-installed copy of this extension doesn't
  double-activate alongside the local --extensionDevelopmentPath build during F5 debugging.
• .claude/rules/testing/unit-tests.md: documented a macOS-specific npx gulp test failure mode
  seen on newer VS Code test-host builds (e.g. 1.131.0) — @vscode/test-electron@2.3.9 expects an
  Electron binary that some releases ship renamed to Code, and the local ln -s workaround for
  that invalidates the app bundle's code signature, requiring an ad hoc re-sign. Both are dev-loop
  fixes only; nothing in the gitignored .vscode-test/ cache is committed.

Test plan

• npx gulp check
• npx gulp lint
• npx gulp test — new/updated unit tests in:
  • src/models/flinkStatement.test.ts (mode getter)
  • src/flinkSql/statementUtils.test.ts (submitFlinkStatement property wiring,
    setFlinkDocumentMetadata)
  • src/commands/documents.test.ts (toggleSnapshotModeForUriCommand, updated reset test)
  • src/codelens/flinkSqlProvider.test.ts (new toggle lens, getSnapshotModeFromMetadata)
• Manually submit a statement with the toggle in each mode and confirm sql.snapshot.mode
  appears (or doesn't) in the submitted statement's properties in CCloud

Relationships

Closes #1849
Closes #1850
Closes #1853

Part of epic #1848

Screenshots

1. Default streaming mode.

2. Switched to snapshot mode.

No changes (yet) to the results viewer, although the snapshot mode statement auto-evolves to COMPLETED state when done. No need to manually stop it. The remaining open tickets in the epic will adjust the results viewer page.

[Copilot]

Pull request overview

Adds per-document support for submitting Confluent Cloud Flink SQL statements in bounded “snapshot” (batch) mode by wiring sql.snapshot.mode: "now" through statement submission and a new Flink SQL CodeLens toggle, plus telemetry and supporting tests.

Changes:

• Introduces FlinkSnapshotMode and a FlinkStatement.mode getter derived from spec.properties["sql.snapshot.mode"].
• Extends submitFlinkStatement() to accept snapshotMode and conditionally set sql.snapshot.mode: "now" for batch execution; persists the chosen mode per-document via URI metadata and a new CodeLens toggle/command.
• Adds unit tests for the new behavior, plus small developer-experience updates (launch.json, test docs).

Reviewed changes

Copilot reviewed 13 out of 13 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
tests/unit/testResources/flinkStatement.ts	Extends test fixture to optionally include sql.snapshot.mode when creating statements.
src/storage/constants.ts	Adds UriMetadataKeys.FLINK_SNAPSHOT_MODE for per-document mode persistence.
src/models/flinkStatement.ts	Adds FlinkSnapshotMode enum and FlinkStatement.mode getter derived from statement properties.
src/models/flinkStatement.test.ts	Adds unit tests for FlinkStatement.mode behavior (absent/now/unknown values).
src/flinkSql/statementUtils.ts	Wires snapshotMode into statement submission properties and persists snapshot mode into URI metadata.
src/flinkSql/statementUtils.test.ts	Adds tests for snapshot-mode property wiring and metadata setting.
src/commands/flinkStatements.ts	Passes snapshot mode into submission and includes it in submission telemetry.
src/commands/documents.ts	Adds toggleSnapshotModeForUriCommand, resets snapshot mode in “Clear Settings”, and registers the new command.
src/commands/documents.test.ts	Adds unit tests for the new toggle command and updates reset expectations.
src/codelens/flinkSqlProvider.ts	Adds “Mode: Streaming/Snapshot” CodeLens and metadata reader helper.
src/codelens/flinkSqlProvider.test.ts	Adds tests for the new CodeLens and getSnapshotModeFromMetadata().
.vscode/launch.json	Prevents double-activation by disabling the marketplace-installed extension during F5 debugging.
.claude/rules/testing/unit-tests.md	Documents a macOS-specific local test-host workaround for newer VS Code builds.

[Copilot]

Pull request overview

Copilot reviewed 14 out of 14 changed files in this pull request and generated no new comments.

[sonarqube-confluent]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
97.9% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube