feat(lang): canonicalize pattern reference syntax and documentation (#170)

[Adityakk9031]

Summary & Motivation

Resolves #170

OpenProse patterns (kind: pattern) are compile-time coordination abstractions. However, as identified in #170, pattern references and instantiations suffered from documentation inconsistencies:

• The canonical section ### Patterns was used in smoke tests and referenced in specs, but missing from the canonical section tables.
• Documentation in prose.md pointed to a nonexistent Forme pattern-expansion section (forme.md, Pattern Expansion).
• Authors and prose compose lacked a single cross-linked definition showing the relationship among use (import/aliases), pattern: (reference), with: (slot binding), and config: (parameters).

This PR canonicalizes pattern references, adds the missing Forme expansion specification, repairs cross-references, and adds a dedicated conformance test suite.

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Key Changes

1. Canonical Section: ### Patterns (skills/open-prose/contract-markdown.md, spec/01-Language.md)

   • Added ### Patterns to the Canonical Sections tables in Contract Markdown and the Language Specification.
   • Clarified that pattern instances are placed in ### Patterns using fenced yaml declarations (- name:, pattern:, with:, config:).

2. Unified Definition of use, pattern:, with:, and config: (skills/open-prose/contract-markdown.md)

   • Defined how use "std/patterns/worker-critic" creates a local alias that pattern: worker-critic can reference directly.
   • Documented how name: defines the expanded node name invoked by ProseScript call {name} in ### Execution.
   • Documented slot binding (with:) and configuration overrides (config:).
   • Provided an end-to-end worked example connecting use, ### Patterns, and ### Execution.

3. Forme Pattern Expansion Specification (skills/open-prose/forme.md)

   • Added the ## Pattern Expansion section detailing the compile-time expansion lifecycle:
     • Resolution: Local contracts, dependency cache (deps/), and std/ shorthand expansion.
     • Slot Validation: Verification that all declared ### Slots are satisfied by responsibilities, functions, or nested pattern instances.
     • Config Validation: Verification and default application against declared ### Config.
     • Instantiation & Delegation Lowering: Lowering ### Delegation into ProseScript execution logic.
     • Inside-Out Nesting & Cycle Prevention: Nested pattern expansion proceeds inside-out; recursive patterns are strictly prohibited.

4. Repaired Cross-References (skills/open-prose/prose.md)

   • Updated references in the VM execution documentation to cleanly point to contract-markdown.md (Patterns) and forme.md, Pattern Expansion.

5. Conformance Tests (tests/open-prose/contract-markdown/patterns.test.ts)

   • Added 6 automated tests validating:
     • Inclusion of ### Patterns in the Canonical Sections tables of contract-markdown.md and 01-Language.md.
     • End-to-end explanation of use, pattern:, with:, and config:.
     • Presence and invariants of ## Pattern Expansion in forme.md.
     • Resolution of cross-references in prose.md.
     • Conformance of smoke test 09-local-pattern.prose.md.

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Verification

• Ran pnpm vitest run tests/open-prose/contract-markdown/patterns.test.ts (6/6 tests passed).
• Ran pnpm vitest run tests/open-prose/forme/forme.test.ts (23/23 tests passed).