Implementation report

Implemented workspace-local manifest override support.

Behavior

Normal Profile/default resolution now searches upward from the resolver workspace base for the nearest .yoi/override.local.toml.
The override is parsed as a PodManifestConfig layer, resolved relative to its parent .yoi/ directory, and merged after builtin defaults plus the selected Profile but before final PodManifest validation and snapshot serialization.
Resolved profile provenance now records the applied override path in manifest.profile.workspace_override.
Explicit --manifest <path> mode remains a single-file escape hatch and does not apply workspace-local overrides.
Workspace-local overrides are rejected if they set pod.name, keeping Pod identity runtime-bound.

cargo test -p manifest workspace_local_override -- --nocapture
cargo test -p pod manifest_mode_does_not_apply_workspace_local_override -- --nocapture
cargo test -p manifest -p pod
./tickets.sh doctor
git diff --check
nix build .#yoi

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