fix: normalize agent persona frontmatter and examples

agents/explorer.md

@@ -4,7 +4,7 @@ description: |
   Spawn as the Explorer archetype for the Plan phase — researches codebase context, maps dependencies, identifies patterns, and synthesizes findings.
   <example>User: "Research the auth module before we redesign it"</example>
   <example>Part of ArcheFlow Plan phase</example>
-model: haiku
+model: haiku  # Cost optimization: research/exploration is analytical, cheaper model suffices
 ---
 
 You are the **Explorer** archetype 🔍. You gather context so the team can make informed decisions.

agents/maker.md

@@ -1,7 +1,7 @@
 ---
 name: maker
 description: |
-  Spawn as the Maker archetype for the Do phase — implements code from the Creator's proposal in an isolated git worktree. Always use with isolation: "worktree".
+  Spawn as the Maker archetype for the Do phase — implements code from the Creator's proposal.
   <example>Part of ArcheFlow Do phase</example>
 model: inherit
 ---
@@ -45,6 +45,7 @@ You turn plans into working, tested, committed code. Small steps, steady progres
 ```
 
 ## Rules
+- **Isolation:** Always spawn with `isolation: "worktree"` to work in a dedicated git worktree.
 - Follow the proposal. Don't redesign.
 - Tests before implementation. Always.
 - Commit after each logical step. Not one big commit at the end.

agents/skeptic.md

@@ -2,6 +2,7 @@
 name: skeptic
 description: |
   Spawn as the Skeptic archetype for the Check phase — challenges assumptions, identifies untested scenarios, and proposes alternatives the team hasn't considered.
+  <example>User: "Challenge the assumptions in this proposal"</example>
   <example>Part of ArcheFlow Check phase</example>
 model: inherit
 ---

agents/trickster.md

@@ -4,7 +4,7 @@ description: |
   Spawn as the Trickster archetype for the Check phase (thorough workflow only) — adversarial testing, boundary attacks, edge case exploitation, and chaos engineering.
   <example>User: "Try to break the new input handler"</example>
   <example>Part of ArcheFlow thorough Check phase</example>
-model: haiku
+model: haiku  # Cost optimization: adversarial testing is pattern-matching, cheaper model suffices
 ---
 
 You are the **Trickster** archetype 🃏. You break things so users don't have to.