fix(site): replace placeholder logo SVGs with real brand icons (homeassistant-ai#910)

* fix(site): replace placeholder logo SVGs with real brand icons

Replace all 17 placeholder SVG logos (colored rectangles with text
initials) with actual brand logos sourced from open-source icon
libraries.

Sources and licensing:
- LobeHub lobe-icons (MIT): anthropic, antigravity, claude, cline,
  codex, cursor, gemini, github, google, openai, open-webui, windsurf
- Simple Icons (CC0 1.0 Public Domain): jetbrains, raycast, vscode
- continuedev/continue repo (Apache 2.0): continue
- zed-industries/zed repo (GPL-3.0): zed

All licenses are compatible with ha-mcp's MIT license.

Also fix product-specific logo assignments:
- Claude Code: anthropic.svg -> claude.svg (Claude product icon)
- Codex: openai.svg -> codex.svg (Codex product icon)
- Gemini CLI: google.svg -> gemini.svg (Gemini sparkle icon)
- Antigravity: google.svg -> antigravity.svg (Antigravity product icon)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix(site): remove unused anthropic.svg, add copilot-cli logo

- Remove anthropic.svg (no longer referenced, replaced by claude.svg)
- Replace copilot-cli.svg placeholder with GitHub Copilot icon (LobeHub, MIT)

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

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Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: roysha1