ADR-0009 — Angular-style components with constructor injection

• Status: Accepted (replaces config-based wiring: agents.config.ts, tool catalog, defineBundle)
• Issue: #87

Context

Adding a tool, an agent or an MCP server touched several places (catalog, config entry, a type list); the structure of a bundle was not visible from its files.

Decision

• Components are annotated classes, one per file, in folders by kind: @Tool, @Agent, @McpServer / @McpTool, @Injectable; a @Bundle module lists agents and servers by class reference — no scanning, no string names, links checked by the compiler.
• Settings in decorators; behaviour through interfaces (ToolHandler); prompts in *.prompt.md next to the agent.
• Dependencies through the constructor, declared in deps and checked by the compiler against the constructor's parameters; the graph and creation order are resolved once at assembly. Chosen over inject() (hidden dependencies, injection context, harder tests) and a single context object.
• @Bundle assembles into the existing bundle config, so the core, profiles, describe and Studio are unchanged. One style everywhere: the previous way was removed.

Consequences

• Tools and agents are classes; tests construct tools with new and fakes.
• Standard decorators give no parameter-type metadata, so deps repeats the constructor's types once — the compiler keeps them in sync.
• Symbol.metadata is not available at runtime on Node 26: metadata lives in the components' own registry.