chore: rename Stirling-Image to ashim across entire codebase

Complete rebrand from Stirling-Image to ashim following the project
move to https://github.com/ashim-hq/ashim.

Changes across 117 files:
- Package scope: @stirling-image/* → @ashim/*
- GitHub URLs: stirling-image/stirling-image → ashim-hq/ashim
- Docker Hub: stirlingimage/stirling-image → ashimhq/ashim
- GitHub Pages: stirling-image.github.io → ashim-hq.github.io
- All branding text: "Stirling Image" → "ashim"
- Docker service/volumes/user: stirling → ashim
- Database: stirling.db → ashim.db
- localStorage keys: stirling-token → ashim-token
- Environment variables: STIRLING_GPU → ASHIM_GPU
- Python cache dirs: .cache/stirling-image → .cache/ashim
- SVG filter IDs, test prefixes, and all other references

apps/web/src/components/files/file-details.tsx

@@ -1,4 +1,4 @@
-import { TOOLS } from "@stirling-image/shared";
+import { TOOLS } from "@ashim/shared";
 import { FileImage } from "lucide-react";
 import { useEffect, useState } from "react";
 import { useNavigate } from "react-router-dom";

apps/web/src/components/files/file-list-item.tsx

@@ -1,4 +1,4 @@
-import { TOOLS } from "@stirling-image/shared";
+import { TOOLS } from "@ashim/shared";
 import type { UserFile } from "@/lib/api";
 import { cn } from "@/lib/utils";
 import { useFilesPageStore } from "@/stores/files-page-store";