feat: agents/skills workflow, agent colors, and CLI/tooling hardening

[protonspy]

Summary

Bundles two things into one PR at the maintainer's request:

1. This session's work — the agents/skills workflow optimization and agent colors.
2. A larger in-progress working-tree changeset that was already present (CLI/tooling hardening, JSON output, a new textutil package, line-ending normalization). It is included as-is; it was not authored in this session.

62 files changed, +2963 / −1823.

This session — agents/skills workflow + colors

• Run the wf-* leads as the main session agent (claude --agent wf-development / wf-product-discovery, or the "agent" setting). This is the only mode where the phase gates can pause for human approval, /clear works, and the leads can spawn fresh-context sub-agents. wf-development also gains the Agent tool so it can actually invoke code-reviewer / security-reviewer / test-designer.
• Parallel (P) task dispatch across boundaries via isolation: worktree — the (P) / _Boundary:_ / _Depends:_ machinery finally has a consumer, while same-boundary tasks stay sequential.
• Prefer the csdd_* MCP tools over the npx form in the leads and the implementer.
• Wire the orphan test-designer into the flow and fix the phantom debugger reference in CLAUDE.md.
• Preload tdd-cycle / verify-change into the implementer via skills: (resolves "delegate to a skill" without the Skill tool); effort: high on both leads.
• Agent colors: distinct color: on the six shipped agents (discovery=purple, development=blue, implementer=green, code-reviewer=red, security-reviewer=orange, test-designer=cyan) plus a validated --color flag on csdd agent create (internal/cli/color.go + unit/integration tests), mirroring the existing --effort pattern. --model help updated to mention fable / full model IDs.

Bundled in-progress WIP (pre-existing, not from this session)

• CLI/core: --help handling, workspace.SafeName guards on agent/skill lookups, new internal/cli/jsonout.go (structured output) and internal/textutil package (shared newline/text helpers), plus touch-ups across cli, web, validator, workspace, manifest, session, templater, mcp-server, and npm.
• Tooling: .golangci.yml, .gitattributes (normalize line endings to LF — this is why many files show large diffs), CI workflow updates.
• Move csdd.html → docs/csdd.html (100% rename).

Verification

• go build ./... ✅
• go test ./... ✅ green in an earlier full run; re-confirmed for the changed/critical packages: cli, textutil, templater, frontmatter, validator, workspace all ✅.
• New --color flag covered by color_test.go (validation set) + agent_color_test.go (create-with-color / no-color / invalid-color-rejected).

Notes

• .idea/ (IDE config, untracked) was deliberately excluded from the commit.
• Four update/clean .old-backup tests are flaky on the /mnt/c WSL filesystem (pass/fail non-deterministically, independent of code) — not introduced here.