feat(#461): add /fullsend namespace prefix for slash commands

[rh-hemartin]

Summary

• Adds /fullsend triage, /fullsend code, /fullsend review, /fullsend fix as namespaced command forms to avoid collisions with other AI tools (e.g., Qodo) that also respond to /review
• Bare commands (/triage, /code, /review, /fix) remain as aliases — no breaking change
• Updates fix.yml sed pattern to strip /fullsend fix prefix from human instructions

Changed files

• internal/scaffold/fullsend-repo/templates/shim-workflow.yaml — namespaced patterns in all 4 slash-command jobs
• .github/workflows/fullsend.yaml — same (this repo's own shim)
• internal/scaffold/fullsend-repo/.github/workflows/fix.yml — instruction prefix stripping
• docs/guides/user/bugfix-workflow.md — updated command table and inline references
• docs/glossary.md — updated Slash Command definition

Test plan

• make lint passes
• go test ./internal/scaffold/... passes
• make go-test passes (all packages)
• Manual: post /fullsend review on a PR comment in an enrolled repo, verify dispatch triggers
• Manual: post /review on same repo, verify bare alias still works

Closes #461

🤖 Generated with Claude Code

[rh-hemartin]

Do we want to remove the normal commands?

[ralphbean]

@rh-hemartin yes, I think we should just remove the old un-namespaced commands.

[ralphbean]

Stylistically, do you like any of these more than another?

• /fullsend triage
• /fullsend:triage
• /fs:triage
• /fs triage

[rh-hemartin]

I like the fully spelled commands with space, but it is a matter of preference.

[ggallen]

We should not use the version with the space. It could cause problems if we want to actually add a prompt after the command.

And we should also not use /fullsend. We had a long discussion about stages where the number of characters was deemed significant (i.e. fix vs. refinement). I don't see why we would then want to add an 8-character prefix on every command.

[ralphbean]

Oh, that's a good point. Like /fix you forgot to add semicolons at the end of every line turns into /fullsend fix you forgot to add... and, the spaces do seem like they'd be easy to get mixed up.

[rh-hemartin]

Superseded by #742 — clean branch with just the /fs- namespace change.