feat(aidd-context): add Kilo support and correct OpenCode rule guidance

No concrete files or tests are named. Start by locating the applicable generators, onboarding, and project-memory detection and generation paths, then review the official OpenCode and Kilo documentation linked or required by the acceptance criteria. Done means all listed detection, preservation, output, skills, workflow, frontmatter, and source-verification criteria pass without implementing flat archives or plugins.

Problem

aidd-context generators must match the current artifact contracts of the selected host tools. The OpenCode rule reference currently claims a native .opencode/rules/ surface that OpenCode does not document. Kilo is absent from the relevant detection and generation references.

Scope

• Correct OpenCode rule guidance: offer AGENTS.md or a Markdown file referenced from opencode.json[c].instructions, preserving user-owned entries.
• Detect Kilo from .kilo/, kilo.json, or kilo.jsonc in applicable generators, onboarding, and project memory.
• Generate Kilo rules as Markdown files referenced from kilo.json[c].instructions, preserving user-owned entries.
• Generate Kilo agents under .kilo/agents/<name>.md with documented frontmatter.
• Generate Kilo workflows as Markdown files under .kilo/commands/ when the user selects Kilo command generation.
• Keep skills in the Agent Skills format. Use .kilo/skills/ for a Kilo-only target; offer .agents/skills/ once only when the user explicitly selects a shared location.
• State that Kilo hooks require a JavaScript or TypeScript plugin.
• Use AGENTS.md as a valid Kilo project-memory wiring surface.

Acceptance criteria

• OpenCode rules are generated through AGENTS.md or opencode.json[c].instructions; no generator claims .opencode/rules/ as a native rule surface.
• A project containing only Kilo signals is detected and proposed by each applicable generator.
• A Kilo rule is referenced from kilo.json[c] without deleting or reordering existing instructions entries.
• A Kilo agent is discoverable from .kilo/agents/ and uses current documented frontmatter.
• Kilo skills use the Agent Skills payload and shared .agents/skills/ placement only after explicit user selection.
• Kilo workflows are generated as Markdown files under .kilo/commands/ when selected.
• Each tool-path claim links to an official source and records its verification date.

Relations

• #789 owns flat OpenCode distribution.
• #868 owns flat Kilo rule distribution and is blocked by #744.
• #744 owns the CLI Kilo profile; this issue does not depend on its draft PR.

Out of scope

• Flat archive emission, including Kilo command distribution; this requires a separate flat-build capability after #744.
• Kilo plugin implementation.
• Kilo lifecycle hooks and plugins, owned by #744.