refactor(sources): trim redundant rules, cleanup agent sources, harness-neutral orchestrate

- Drop rules/02-responses.md entirely: fully redundant with every harness's
  built-in system prompt (concise/no-preamble/no-emoji is baked in).
- Trim 04-tools.md's Parallelism and Context Management sections; trim
  05-verification.md's "run tests" bullet. All covered by harness defaults.
- Scope 01-session.md to claude only (memory/ hierarchy is Claude-specific).
- Update schemas/team.schema.json const-pin to match the new rules.order.
- Strip vestigial Claude-style YAML frontmatter from agents/*.md sources
  (extract_body was already discarding it; TEAM.yaml is the real source).
- Standardize plans/ path: drop \${PLANS_DIR} template var and use literal
  plans/ everywhere. Claude/codex/opencode now share one plans convention.
- Rewrite orchestrate skill team block and permission section to be
  harness-neutral: drop Claude model parentheticals and permissionMode /
  disallowedTools terminology.
- Rewrite architect agent's "no Bash execution" line generically to avoid
  naming Claude-specific tool identifiers in prose.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

schemas/team.schema.json

@@ -470,7 +470,6 @@
           "uniqueItems": true,
           "const": [
             "01-session",
-            "02-responses",
             "03-git",
             "04-tools",
             "05-verification",
@@ -482,7 +481,6 @@
           "additionalProperties": false,
           "required": [
             "01-session",
-            "02-responses",
             "03-git",
             "04-tools",
             "05-verification",
@@ -499,16 +497,6 @@
                 }
               ]
             },
-            "02-responses": {
-              "allOf": [
-                { "$ref": "#/$defs/rule_item" },
-                {
-                  "properties": {
-                    "id": { "const": "02-responses" }
-                  }
-                }
-              ]
-            },
             "03-git": {
               "allOf": [
                 { "$ref": "#/$defs/rule_item" },