feat: expose PROJECT_DIR global for ake files

docs/Ake.md

@@ -98,6 +98,12 @@ ake greetings   # finds ../ake and runs it in the project directory
 
 The working directory is automatically set to the project directory (where the ake file lives), so `$` commands always run relative to the project root.
 
+## Global Variables
+
+```ts
+PROJECT_DIR  // absolute path to the project dir
+```
+
 ## Multiple Ake Files
 
 Any file named `ake<suffix>` or `ake<suffix>.ts` is supported.

docs/Global Commands.md

@@ -76,6 +76,7 @@ $`cat ${files}`                   // cat a.txt b.txt
 ## Global Variables
 
 ```ts
-app      // Command instance for defining CLI metadata and commands
-$        // Shell command tagged template
+app          // Command instance for defining CLI metadata and commands
+$            // Shell command tagged template
+PROJECT_DIR  // ake only: absolute path to the project dir (where the ake file lives)
 ```

src/Command.ts

@@ -132,6 +132,7 @@
     }
     const projectDir = getProjectDir(scriptPath)
     process.chdir(projectDir)
+    ;(globalThis as any).PROJECT_DIR = projectDir
   }
 
   async parse(argv: string[]): Promise<void> {
@@ -425,7 +426,7 @@
         })
       }
       if (c.commands.length > 0) {
         const childPrefix = prefix ? `${prefix} ${c._name}` : c._name!
         result.push(...c.#collectCommands(childPrefix))
       }
     }

src/globals.d.ts

@@ -4,4 +4,5 @@ import type { $ as Shell } from './spawn'
 declare global {
   var app: Command
   var $: typeof Shell
+  var PROJECT_DIR: string
 }