feat: auto-resolve @path references in skill templates to absolute paths

Skill loaders previously only told agents that @path references are
relative to the skill directory, but agents often failed to resolve
them. Now @path/with/slash patterns are automatically expanded to
absolute paths during template construction.

src/features/opencode-skill-loader/async-loader.ts

@@ -5,6 +5,7 @@ import yaml from "js-yaml"
 import { parseFrontmatter } from "../../shared/frontmatter"
 import { sanitizeModelField } from "../../shared/model-sanitizer"
 import { resolveSymlink, isMarkdownFile } from "../../shared/file-utils"
+import { resolveSkillPathReferences } from "../../shared/skill-path-resolver"
 import type { CommandDefinition } from "../claude-code-command-loader/types"
 import type { SkillScope, SkillMetadata, LoadedSkill } from "./types"
 import type { SkillMcpConfig } from "../skill-mcp-manager/types"
@@ -90,11 +91,12 @@ export async function loadSkillFromPathAsync(
     const isOpencodeSource = scope === "opencode" || scope === "opencode-project"
     const formattedDescription = `(${scope} - Skill) ${originalDescription}`
 
+    const resolvedBody = resolveSkillPathReferences(body.trim(), resolvedPath)
     const wrappedTemplate = `<skill-instruction>
 Base directory for this skill: ${resolvedPath}/
 File references (@path) in this skill are relative to this directory.
 
-${body.trim()}
+${resolvedBody}
 </skill-instruction>
 
 <user-request>