docs: add Linear integration, new features, and workflow CLI commands

[zhubert]

Summary

Updates documentation site and README to reflect recent feature additions including Linear issue integration, fork & compare, broadcast, and workflow configuration.

Changes

• Add workflow init, workflow validate, and workflow visualize CLI commands to README
• Add Linear as a supported issue provider alongside GitHub Issues and Asana
• Add three new feature cards to docs site: fork & compare, broadcast, and workflow config
• Fix broken link to plural-agent repo

Test plan

• Verify README renders correctly with new CLI commands section
• Open docs/index.html locally and confirm the three new feature cards display properly
• Confirm the plural-agent link points to the correct GitHub URL

Fixes #313

[zhubert]

Session Transcript

User:
GitHub Issue #313: Update all docs

https://github.com/zhubert/plural/issues/313

docs/index.html and Claude and readme, thank you!

Assistant:
● Using ToolSearch(ToolSearch: select:Read,Glob,Bash)
● Searching(Glob: *.md)
● Searching(Glob: docs/**)
● Reading(Read: README.md)
● Reading(Read: index.html)

Now I have a clear picture. Let me identify the gaps:

**docs/index.html:**
- Issue integration card only mentions GitHub and Asana, missing Linear
- `plural-agent` link points to `zhubert.com` not GitHub
- Missing feature cards for: fork sessions, broadcast, workflow config

**README.md:**
- Missing `plural workflow` CLI commands (init, validate, visualize)

**CLAUDE.md:**
- Looks comprehensive already

Let me make these updates:
● Using ToolSearch(ToolSearch: select:Edit,TodoWrite)
● Editing(Edit: index.html)

Now fix the plural-agent URL and add new feature cards:
● Editing(Edit: index.html)

Now fix the plural-agent link to point to GitHub:
● Editing(Edit: index.html)
● Editing(Edit: README.md)
● Running(Bash: git diff --stat)
● Running(Bash: git status && git diff --stat HEAD)
● Running(Bash: git config --global --add safe.direct...)
● Running(Bash: git add README.md docs/index.html && ...)

Done. Here's a summary of what was updated:

**docs/index.html:**
- Updated issue integration feature card to mention GitHub, Asana, **and Linear**
- Added 3 new feature cards: **fork & compare**, **broadcast**, and **workflow config**
- Fixed `plural-agent` link from `zhubert.com/plural-agent` → `github.com/zhubert/plural-agent`

**README.md:**
- Added `plural workflow init/validate/visualize` commands to the CLI Reference section

**CLAUDE.md** was already comprehensive and didn't need changes.

[ghost]

Documentation updates look good. All changes are accurate and well-formatted. The three new feature cards fit naturally into the existing grid layout, CLI commands are documented consistently, and the plural-agent link now correctly points to the GitHub repository.