feat: add conversational Telos spec skill

[jamesdoh0109]

Summary

• add a dedicated telos-spec skill for conversational creation, improvement, review, and fast drafting of Telos specs
• keep telos-cli focused on operational workflows and document the handoff between the two skills
• package, publish, promote, install, and verify both skills for Codex and Claude Code
• add transactional installer safeguards for upgrades, rollback, concurrency, symlinks, legacy installations, and custom destinations
• exclude the installer ownership marker from bundles produced by telos push

Usage

• Codex: explicitly invoke $telos-spec
• Claude Code: explicitly invoke /telos-spec

Explicit invocation is documented because implicit natural-language routing is not consistently reliable across clients.

Verification

• built both release skill archives and verified source/archive parity
• passed the complete release installer harness, including rollback, concurrency, malformed archives, symlinks, migration, custom paths, and failure injection
• passed go test ./...
• passed go vet ./...
• passed go test -race ./...
• passed POSIX sh and Dash syntax checks
• passed skill validation and YAML parsing
• smoke-tested explicit invocation in isolated Codex and Claude Code environments
• received GO verdicts from three adversarial reviews, with no remaining P0/P1 findings

[jamesdoh0109]

lgtm