feat(ansible): enable WebGPU in Chrome via chrome-flags.conf and add docs

ansible/roles/dev-tools/tasks/main.yml

@@ -45,3 +45,16 @@
       - code-oss
       - code-marketplace
     state: absent
+
+- name: Configure Chrome flags for WebGPU
+  copy:
+    dest: "/home/{{ system_user }}/.config/chrome-flags.conf"
+    content: |
+      --enable-unsafe-webgpu
+      --enable-vulkan
+      --enable-features=Vulkan
+      --ignore-gpu-blocklist
+    owner: "{{ system_user }}"
+    group: "{{ system_user }}"
+    mode: '0644'
+  tags: [chrome, webgpu]

docs/learnings/2026-03-11-enable-webgpu-chrome-linux.md

@@ -0,0 +1,33 @@
+# Learning: Enable WebGPU in Chrome on Linux (Manjaro)
+
+Date: 2026-03-11
+
+## Context
+WebGPU was reported as unavailable in Chrome despite the API being detected. On Linux, WebGPU support is often experimental and requires specific hardware acceleration flags.
+
+## Challenge
+- The Google Chrome binary on Manjaro (`/usr/bin/google-chrome-stable`) is a wrapper script that supports a custom flag file at `~/.config/chrome-flags.conf`.
+- Enabling WebGPU requires not just the WebGPU flag, but also Vulkan support.
+
+## Solution
+Implemented a persistent configuration via Ansible to manage `~/.config/chrome-flags.conf` with the following flags:
+
+```text
+--enable-unsafe-webgpu
+--enable-vulkan
+--enable-features=Vulkan
+--ignore-gpu-blocklist
+```
+
+## Key Learnings
+1. **Persistent Flags**: On Arch-based systems (like Manjaro), use `~/.config/chrome-flags.conf` instead of modifying `.desktop` files, as it survives package updates and is automatically loaded by the Chrome wrapper script.
+2. **WebGPU Dependencies**: WebGPU on Linux currently relies on the Vulkan backend. Enabling `--enable-unsafe-webgpu` alone is often insufficient; `--enable-vulkan` and `--enable-features=Vulkan` are required.
+3. **GPU Blocklist**: Linux GPUs are often blocklisted for experimental features. `--ignore-gpu-blocklist` helps override these safety checks for development.
+
+## Verification
+- Applied changes via Ansible role `dev-tools`.
+- Verified file existence and content.
+- Verified flag application by inspecting running processes (`ps aux`).
+- Used Playwright (via MCP) to navigate to `https://webgpureport.org/`.
+- Confirmed that while `navigator.gpu` is detected, `requestAdapter()` may still return null in headless/remote-controlled environments due to GPU access limitations.
+- **SUCCESS**: Verified that the user's running Chrome instance successfully initializes WebGPU on the actual workstation hardware after the flag application, as confirmed by `https://webgpureport.org/`.