feat: add /opsx:explore command for exploratory thinking (Fission-AI#467)

Wire up the explore skill and slash command templates to the
artifact-experimental-setup command. This adds /opsx:explore as
a thinking partner mode for exploring ideas, investigating problems,
and clarifying requirements before committing to a change.

Changes:
- Add imports for getExploreSkillTemplate and getOpsxExploreCommandTemplate
- Add explore skill to skills array (generates openspec-explore/SKILL.md)
- Add explore command to commands array (generates opsx/explore.md)
- Add /opsx:explore to CLI usage message
- Update docs/experimental-workflow.md with explore command

Author: TabishB

docs/experimental-workflow.md

@@ -82,6 +82,7 @@ This creates skills in `.claude/skills/` that Claude Code auto-detects.
 
 | Command | What it does |
 |---------|--------------|
+| `/opsx:explore` | Think through ideas, investigate problems, clarify requirements |
 | `/opsx:new` | Start a new change |
 | `/opsx:continue` | Create the next artifact (based on what's ready) |
 | `/opsx:ff` | Fast-forward — create all planning artifacts at once |
@@ -91,6 +92,12 @@ This creates skills in `.claude/skills/` that Claude Code auto-detects.
 
 ## Usage
 
+### Explore an idea
+```
+/opsx:explore
+```
+Think through ideas, investigate problems, compare options. No structure required - just a thinking partner. When insights crystallize, transition to `/opsx:new` or `/opsx:ff`.
+
 ### Start a new change
 ```
 /opsx:new
@@ -520,6 +527,7 @@ Run `openspec schemas` to see available schemas.
 
 ## Tips
 
+- Use `/opsx:explore` to think through an idea before committing to a change
 - `/opsx:ff` when you know what you want, `/opsx:continue` when exploring
 - During `/opsx:apply`, if something's wrong — fix the artifact, then continue
 - Tasks track progress via checkboxes in `tasks.md`

src/commands/artifact-workflow.ts

@@ -28,7 +28,7 @@ import {
   type SchemaInfo,
 } from '../core/artifact-graph/index.js';
 import { createChange, validateChangeName } from '../utils/change-utils.js';
-import { getNewChangeSkillTemplate, getContinueChangeSkillTemplate, getApplyChangeSkillTemplate, getFfChangeSkillTemplate, getSyncSpecsSkillTemplate, getArchiveChangeSkillTemplate, getOpsxNewCommandTemplate, getOpsxContinueCommandTemplate, getOpsxApplyCommandTemplate, getOpsxFfCommandTemplate, getOpsxSyncCommandTemplate, getOpsxArchiveCommandTemplate } from '../core/templates/skill-templates.js';
+import { getExploreSkillTemplate, getNewChangeSkillTemplate, getContinueChangeSkillTemplate, getApplyChangeSkillTemplate, getFfChangeSkillTemplate, getSyncSpecsSkillTemplate, getArchiveChangeSkillTemplate, getOpsxExploreCommandTemplate, getOpsxNewCommandTemplate, getOpsxContinueCommandTemplate, getOpsxApplyCommandTemplate, getOpsxFfCommandTemplate, getOpsxSyncCommandTemplate, getOpsxArchiveCommandTemplate } from '../core/templates/skill-templates.js';
 import { FileSystemUtils } from '../utils/file-system.js';
 
 // -----------------------------------------------------------------------------
@@ -793,6 +793,7 @@ async function artifactExperimentalSetupCommand(): Promise<void> {
     const commandsDir = path.join(projectRoot, '.claude', 'commands', 'opsx');
 
     // Get skill templates
+    const exploreSkill = getExploreSkillTemplate();
     const newChangeSkill = getNewChangeSkillTemplate();
     const continueChangeSkill = getContinueChangeSkillTemplate();
     const applyChangeSkill = getApplyChangeSkillTemplate();
@@ -801,6 +802,7 @@ async function artifactExperimentalSetupCommand(): Promise<void> {
     const archiveChangeSkill = getArchiveChangeSkillTemplate();
 
     // Get command templates
+    const exploreCommand = getOpsxExploreCommandTemplate();
     const newCommand = getOpsxNewCommandTemplate();
     const continueCommand = getOpsxContinueCommandTemplate();
     const applyCommand = getOpsxApplyCommandTemplate();
@@ -810,6 +812,7 @@ async function artifactExperimentalSetupCommand(): Promise<void> {
 
     // Create skill directories and SKILL.md files
     const skills = [
+      { template: exploreSkill, dirName: 'openspec-explore' },
       { template: newChangeSkill, dirName: 'openspec-new-change' },
       { template: continueChangeSkill, dirName: 'openspec-continue-change' },
       { template: applyChangeSkill, dirName: 'openspec-apply-change' },
@@ -840,6 +843,7 @@ ${template.instructions}
 
     // Create slash command files
     const commands = [
+      { template: exploreCommand, fileName: 'explore.md' },
       { template: newCommand, fileName: 'new.md' },
       { template: continueCommand, fileName: 'continue.md' },
       { template: applyCommand, fileName: 'apply.md' },
@@ -898,6 +902,7 @@ ${template.content}
     console.log('  • "Implement the tasks for this change"');
     console.log();
     console.log('  ' + chalk.cyan('Slash Commands') + ' for explicit invocation:');
+    console.log('  • /opsx:explore - Think through ideas, investigate problems');
     console.log('  • /opsx:new - Start a new change');
     console.log('  • /opsx:continue - Create the next artifact');
     console.log('  • /opsx:apply - Implement tasks');