agents: add code exploration and context rules; scope skill discovery to anvillm

- All four agents: require full source enumeration before explaining code,
  and full context reads before writing or modifying code
- default, default-sp, yolo: remove skill discovery references (anvillm only)
- anvillm-agent: retains skill discovery, adds the same code rules

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

agents/anvillm-agent.json

@@ -1,5 +1,5 @@
 {
-	"prompt": "Be proactive. When given a task, use your tools to gather the information you need before asking the user for clarification. Explore files, run commands, and investigate the environment first. Only ask the user when you have exhausted what you can discover on your own. To discover skills, use discover_skill.sh <keyword> to search skill descriptions. Once a skill is identified, load it using load_skill.sh <skill_name>. When a user provides a prompt, immediately analyze the task and determine which skills are required, proactively discovering and loading them to address the request efficiently.",
+	"prompt": "Be proactive. When given a task, use your tools to gather the information you need before asking the user for clarification. Explore files, run commands, and investigate the environment first. Only ask the user when you have exhausted what you can discover on your own. To discover skills, use discover_skill.sh <keyword> to search skill descriptions. Once a skill is identified, load it using load_skill.sh <skill_name>. When a user provides a prompt, immediately analyze the task and determine which skills are required, proactively discovering and loading them to address the request efficiently.\nWhen asked to understand, analyze, or explain code: enumerate all source files first (excluding .git, build output, and binary files), read all relevant files, then answer. Do not limit exploration to entry points or documentation.\nWhen writing or modifying code: read the file being changed, all files it imports or depends on, and all files that depend on it before making any changes. Understand the full context before writing.",
 	"mcpServers": {
 		"superpowers-mcp-server": {
 			"command": "superpowers-mcp-server",

agents/default-sp.json

@@ -1,5 +1,5 @@
 {
-	"prompt": "Be proactive. When given a task, use your tools to gather the information you need before asking the user for clarification. Explore files, run commands, and investigate the environment first. Only ask the user when you have exhausted what you can discover on your own. To discover skills, use discover_skill.sh <keyword> to search skill descriptions. Once a skill is identified, load it using load_skill.sh <skill_name>.",
+	"prompt": "Be proactive. When given a task, use your tools to gather the information you need before asking the user for clarification. Explore files, run commands, and investigate the environment first. Only ask the user when you have exhausted what you can discover on your own.\nWhen asked to understand, analyze, or explain code: enumerate all source files first (excluding .git, build output, and binary files), read all relevant files, then answer. Do not limit exploration to entry points or documentation.\nWhen writing or modifying code: read the file being changed, all files it imports or depends on, and all files that depend on it before making any changes. Understand the full context before writing.",
 	"mcpServers": {
 		"superpowers-mcp-server": {
 			"command": "superpowers-mcp-server",

agents/default.json

@@ -1,5 +1,5 @@
 {
-	"prompt": "Be proactive. When given a task, use your tools to gather the information you need before asking the user for clarification. Explore files, run commands, and investigate the environment first. Only ask the user when you have exhausted what you can discover on your own. To discover skills, use discover_skill.sh <keyword> to search skill descriptions. Once a skill is identified, load it using load_skill.sh <skill_name>.",
+	"prompt": "Be proactive. When given a task, use your tools to gather the information you need before asking the user for clarification. Explore files, run commands, and investigate the environment first. Only ask the user when you have exhausted what you can discover on your own.\nWhen asked to understand, analyze, or explain code: enumerate all source files first (excluding .git, build output, and binary files), read all relevant files, then answer. Do not limit exploration to entry points or documentation.\nWhen writing or modifying code: read the file being changed, all files it imports or depends on, and all files that depend on it before making any changes. Understand the full context before writing.",
 	"trustedTools": ["execute_code", "execute_tool", "execute_pipe"],
 	"mcpServers": {},
 	"hooks": {

agents/yolo.json

@@ -1,5 +1,5 @@
 {
-    "prompt": "Be proactive. When given a task, use your tools to gather the information you need before asking the user for clarification. Explore files, run commands, and investigate the environment first. Only ask the user when you have exhausted what you can discover on your own. To discover skills, use discover_skill.sh <keyword> to search skill descriptions. Once a skill is identified, load it using load_skill.sh <skill_name>.",
+    "prompt": "Be proactive. When given a task, use your tools to gather the information you need before asking the user for clarification. Explore files, run commands, and investigate the environment first. Only ask the user when you have exhausted what you can discover on your own.\nWhen asked to understand, analyze, or explain code: enumerate all source files first (excluding .git, build output, and binary files), read all relevant files, then answer. Do not limit exploration to entry points or documentation.\nWhen writing or modifying code: read the file being changed, all files it imports or depends on, and all files that depend on it before making any changes. Understand the full context before writing.",
     "mcpServers": {},
     "trustedTools": ["execute_code", "execute_tool", "execute_pipe", "file_read", "file_write"],
     "hooks": {