1.0 prep: experiment-flag cleanup and release polish

[clintmod]

Goal

Resolve the non-test items that are blocking a 1.0 framing. These are independent of the two test-coverage streams.

Tasks

• Decide fate of the EnvPrecedence experiment flag — if shipped, remove the gate from internal/experiments/ and stop toggling it in tests; if still experimental, that is itself a 1.0 blocker and needs a SPEC/README note
• Fix go install version string — inject internal/version.version via -ldflags for non-goreleaser builds, or fall back to debug.ReadBuildInfo() in main.go
• Audit or flag-gate RITE_X_REMOTE_TASKFILES — either audit the inherited code paths or add a louder "experimental, unaudited" warning on use
• Republish a rite-scoped JSON schema at clintmod.github.io/rite/schema.json and re-enable the deleted lint-jsonschema CI job

Parallel-safety

Touches internal/experiments/, main.go/cmd/, website/, and .github/workflows/. Disjoint from the two test-coverage streams.

Part of the 1.0 readiness audit.

[clintmod]

Filed against the wrong repo — refiling on clintmod/rite. Apologies for the noise.