feat(billing): teach Shira the GreenInvoiceBilling extension surface

Adds two new tool categories — billing (10 tools) and legal_aid (6 tools)
— so Shira can drive the full Green Invoice flow: list unbilled activities,
manage charges (approve/cancel/calculate), build draft invoices from
activities, sync to Green Invoice, plus the legal-aid sub-flow (proforma,
mark-submitted, monthly 320 wrap-up, prepare-email, resubmit rejected).

Wires both registrars into agent_runner with allowed_toolsets gating, and
extends TOOL_RULES so Shira (a) shows draft totals before creating, (b)
treats send_invoice_to_green_invoice as irreversible and demands explicit
confirmation, and (c) never marks a legal-aid proforma as submitted
without an explicit request number from the user.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

api/services/agent_runner.py

@@ -14,6 +14,8 @@ from mcp_server.tools.document_tools import register_document_tools
 from mcp_server.tools.legal_tools import register_legal_tools
 from mcp_server.tools.legal_kb_tools import register_legal_kb_tools
 from mcp_server.tools.signature_tools import register_signature_tools
+from mcp_server.tools.billing_tools import register_billing_tools
+from mcp_server.tools.legal_aid_tools import register_legal_aid_tools
 from api.services.skills import register_skill_tools
 from api.services.memory import register_memory_tools
 from api.services.delegate import register_delegate_tool
@@ -111,7 +113,7 @@ class AgentRunner:
         Args:
             depth: Current delegation depth. 0 = main conversation, 1 = child agent.
             blocked_tools: Tool names to exclude (used by delegation to prevent recursion).
-            allowed_toolsets: If set, only register tools from these categories (crm, documents, legal).
+            allowed_toolsets: If set, only register tools from these categories (crm, documents, legal, signature, billing, legal_aid).
             on_event: Optional sync callback fired between iterations and tool calls.
                 Receives a dict {type, label, ...} where type ∈ {thinking,
                 tool_start, tool_done, tool_error}. Used by /kb/ask/stream
@@ -150,6 +152,10 @@ class AgentRunner:
             )
         if should_register_all or "signature" in (allowed_toolsets or []):
             register_signature_tools(tools_registry, crm, case_id, user_id, context)
+        if should_register_all or "billing" in (allowed_toolsets or []):
+            register_billing_tools(tools_registry, crm, case_id, user_id, context)
+        if should_register_all or "legal_aid" in (allowed_toolsets or []):
+            register_legal_aid_tools(tools_registry, crm, case_id, user_id, context)
 
         # Phase 3 tools (only for main conversation, not child agents)
         if depth == 0:

api/services/prompt_builder.py

@@ -55,6 +55,11 @@ TOOL_RULES = (
     "- When user asks to summarize multiple documents or the entire case folder — use read_multiple_documents with all relevant file paths.\n"
     "- When user asks to rename or organize files — use batch_rename_documents with an array of rename operations.\n"
     "- TEMPLATE GENERATION: When user asks to generate/create a document from a template — use generate_from_template. The templateId comes from availableTemplates in your context.\n"
+    "- BILLING (חיוב/חשבונית): When user asks about billable activities, charges, or invoices — start with list_unbilled_activities for a case, or list_charges for charge status views. Show the user a summary BEFORE creating an invoice.\n"
+    "- BILLING — invoice creation: create_invoice_from_activities only creates a Draft. It does NOT auto-send to Green Invoice. Always show the user the draft amount and ask if they want to send it before calling send_invoice_to_green_invoice.\n"
+    "- BILLING — irreversible: send_invoice_to_green_invoice issues an official tax document and CANNOT be undone. Require an explicit instruction like 'תשלחי לחשבונית ירוקה', not a vague 'כן'. If unsure, ask again.\n"
+    "- BILLING — charges: A Charge moves Pending → Approved → (invoiced via create_invoice_from_activities). Cancel only if user explicitly asks. Never approve in bulk without listing the IDs and amounts first.\n"
+    "- LEGAL AID (סיוע משפטי): the flow is recorded charges → create_legal_aid_proforma → user submits manually at the official site → mark_legal_aid_submitted with the request number → payment report ingestion (automated) → create_monthly_legal_aid_invoice for the month. NEVER call mark_legal_aid_submitted without an explicit request number provided by the user. Use legal_aid_monthly_summary to preview before create_monthly_legal_aid_invoice.\n"
 )
 
 LEGAL_ASSISTANCE_PROMPT = (