docs: add TakoAPI directory badge

[oratis]

Hi! 👋 TencentDB-Agent-Memory is listed in the TakoAPI open agent directory — a free, open catalog that helps people discover AI-agent projects ("one API to discover all agents").

Your listing: https://takoapi.com/agents/tencentcloud-tencentdb-agent-memory

This PR adds a small badge near the top of the README that links back to that listing, so visitors can find the directory entry. It's entirely optional — if you'd prefer not to include it, just close this PR (no hard feelings, and apologies for the noise).

No tracking and no obligations. Thanks for building TencentDB-Agent-Memory! 🙏

[Maxwell-Code07]

Thank you for your contribution. We will internally review this PR and provide feedback as soon as possible.

[YOMXXX]

Review note: I cannot approve this as-is because the badge is inserted inside a fenced bash configuration block.

Current placement means the Markdown badge becomes part of the shell/config snippet under # ============ Configuration Parameters ============, which is misleading for users who copy the example.

Please move the TakoAPI badge outside the code block, ideally near the project badges/top metadata or immediately before/after the relevant documentation section, so it renders as Markdown instead of appearing as shell text.

Verification run:

• git diff --check $(git merge-base main HEAD)..HEAD -- README.md passed, so this is a content/placement issue rather than whitespace.