feat(lanes): add pipeline-template picker to the Workspace lane header

Lets a lane's pipeline template be switched live from the dashboard
(the same PATCH /api/lanes/:id the CLI's `ccam lanes pipeline` uses),
so lanes created before the picker shipped don't need the terminal.
Both ship-feature skills now force their own template before their
first `ccam stage` call, so the human never has to pick correctly at
lane creation.

.claude/skills/ship-feature/SKILL.md

@@ -19,6 +19,13 @@ Each phase below starts with `ccam stage <node>`, which is what puts the phase
 on the lane's pipeline map. The nodes are the `default` template's:
 `intake → plan → implement → tests → review → gate → ship → done`.
 
+Set the template yourself, don't rely on how the lane was created: before your
+first `ccam stage` call, run `ccam lanes pipeline default` (no id needed —
+resolves from `cwd`; a no-op if the lane is already on it). This is what makes
+the choice invisible to the human — whichever of `ship-feature` or
+`ship-feature-lane` actually runs is what decides the template, not a picker
+they have to get right in advance.
+
 `ccam stage` needs a lane owning the current directory. If it reports no lane,
 this repo was never adopted (`ccam lanes add --cwd $(pwd)` fixes it) — carry on
 with the workflow and skip the stage calls; they are reporting, not control