feat: Add TealTiger governance integration for deterministic policy enforcement

[nagasatish007]

Issue Body

Summary

We've published tealtiger-adk — a standalone governance callback package that integrates with Google ADK's before_tool_callback / after_tool_callback hooks to provide deterministic policy enforcement, PII detection, cost tracking, and audit evidence for ADK agents.

What it does

tealtiger-adk provides a TealTigerCallback class that plugs into ADK's existing callback system:

from google.adk import Agent
from tealtiger_adk import TealTigerCallback

governance = TealTigerCallback(
    policies=[
        {"type": "pii_block", "categories": ["ssn", "credit_card"]},
        {"type": "cost_limit", "max_per_session": 5.00},
        {"type": "tool_allowlist", "allowed": ["google_search", "code_*"]},
        {"type": "secret_detection"},
    ],
    mode="ENFORCE",  # OBSERVE | MONITOR | ENFORCE
)

agent = Agent(
    model="gemini-2.0-flash",
    tools=[google_search, code_execution],
    before_tool_callback=governance.before_tool,
    after_tool_callback=governance.after_tool,
)

Key Features

Feature	Description
PII Detection	Block SSN, credit cards, emails, phone numbers, IP addresses
Secret Detection	Prevent API key leaks (OpenAI, GitHub, AWS, Google, Groq)
Cost Tracking	Per-session budget limits with automatic enforcement
Tool Allowlisting	Restrict tools with wildcard support
Kill Switch	Instant freeze/unfreeze of agent tool access
Audit Trail	Structured decision log with correlation IDs and risk scores

Architecture

• Zero LLM in governance path — all evaluation is deterministic regex/rule-based
• Sub-millisecond overhead — <0.1ms per evaluation (30 tests pass in <1s total)
• Three modes: OBSERVE (log only), MONITOR (log + warn), ENFORCE (log + block)
• Native ADK integration — uses before_tool_callback/after_tool_callback exactly as designed

Why this matters for ADK users

1. Compliance — Prove governance was applied (audit trail with correlation IDs)
2. Safety — Prevent PII/secrets from leaking through tool calls
3. Cost control — Budget limits prevent runaway agent costs
4. Kill switch — Emergency stop without redeploying

Installation

pip install tealtiger-adk

Links

• PyPI: https://pypi.org/project/tealtiger-adk/
• Source: https://github.com/agentguard-ai/tealtiger/tree/main/packages/tealtiger-adk
• TealTiger: https://tealtiger.ai
• Docs: https://docs.tealtiger.ai/integrations/google-adk

Request

Would the team be open to:

1. Listing tealtiger-adk in the ADK ecosystem/integrations documentation?
2. Any feedback on how we're using the callback API — happy to adjust to better fit ADK patterns.

We're part of NVIDIA Inception and have existing integrations with LangChain, Haystack, AG2, CrewAI, Strands, and PydanticAI.

Labels

enhancement, integration

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