feat: add readable session identifiers

[rishabhraj36]

Description

Adds readable, Profile-scoped browser Session identifiers across local and hosted CLI surfaces.

• requires a human name for Session creation;
• normalizes names and appends a two-character unambiguous suffix;
• uses the fixed adapter-default Session for adapter commands without an explicit selector;
• removes opaque Session IDs and cross-Profile owner discovery;
• preserves lease/run authority when readable IDs are reused;
• updates product documentation and generated agent skills.

Related Cloud PR: agentrhq/webcmd-cloud#65. This CLI PR should land first.

Type of Change

• 🐛 Bug fix
• ✨ New feature
• 🌐 New site adapter
• 📝 Documentation
• ♻️ Refactor
• 🔧 CI / build / tooling

Checklist

• I ran the checks relevant to this PR
• I updated tests or docs if needed
• I included output or screenshots when useful
• If I edited skill-src/, I ran make build and committed skills/

Adapter Notes

• Updated generated or lean docs when command discoverability changed
• Used positional args for the command's primary subject unless a named flag is clearly better
• Normalized expected adapter failures to CliError subclasses instead of raw Error

Verification

• Full unit project: 164 files passed; 2,953 tests passed; 1 skipped.
• npm run typecheck: passed.
• npm run build: passed.
• Canonical/generated skill verification: passed.
• Independent task reviews and final branch review: approved.

Screenshots / Output

Not applicable; this changes CLI/session behavior and documentation.

[github-actions]

🟠 Maintainer review suggested — low confidence

The automated review could not reach a fully supported conclusion.

This review is advisory and does not block merging.