fix: merge main (v0.161.0) into classification feature branch

Resolve all 40 merge conflicts from merging origin/main into the
classification feature branch. Key resolutions:

- Auto-generated files (BUILD_DATE, VERSION, etc.): use main's version
- API tokens: take main's version (token expiry, reactivation, hard-delete)
- Auth: take main's Dropbox credential sharing + token expiry checking
- Config: take main's social_auth_dropbox_use_global_credentials option
- Files API: take main's improved duplicate handling + rate limiting
- Models: keep ClassificationRuleModel alongside main's new models
- Mobile: take main's mature implementation
- Templates/translations: take main's versions (device deletion, reactivation keys)
- Migration: renumber 038_add_classification_rules → 039_add_classification_rules
  to chain after main's 038_add_api_token_expires_at
- Requirements: take main's version (adds segno QR library)
- Tests: take main's more complete token tests, keep classification imports

migrations/versions/039_add_classification_rules.py

@@ -0,0 +1,46 @@
+"""Add classification_rules table for custom document classification rules.
+
+Revision ID: 039_add_classification_rules
+Revises: 038_add_api_token_expires_at
+Create Date: 2026-03-17
+"""
+
+from typing import Union
+
+import sqlalchemy as sa
+from alembic import op
+
+revision: str = "039_add_classification_rules"
+down_revision: Union[str, None] = "038_add_api_token_expires_at"
+depends_on: Union[str, None] = None
+
+
+def upgrade() -> None:
+    """Create classification_rules table."""
+    op.create_table(
+        "classification_rules",
+        sa.Column("id", sa.Integer(), nullable=False),
+        sa.Column("owner_id", sa.String(), nullable=True),
+        sa.Column("name", sa.String(255), nullable=False),
+        sa.Column("category", sa.String(100), nullable=False),
+        sa.Column("rule_type", sa.String(50), nullable=False),
+        sa.Column("pattern", sa.String(1000), nullable=False),
+        sa.Column("priority", sa.Integer(), nullable=False, server_default="0"),
+        sa.Column("case_sensitive", sa.Boolean(), nullable=False, server_default="0"),
+        sa.Column("enabled", sa.Boolean(), nullable=False, server_default="1"),
+        sa.Column("created_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
+        sa.Column("updated_at", sa.DateTime(timezone=True), server_default=sa.func.now()),
+        sa.PrimaryKeyConstraint("id"),
+        sa.UniqueConstraint("owner_id", "name", name="uq_classification_rules_owner_name"),
+    )
+    op.create_index("ix_classification_rules_id", "classification_rules", ["id"])
+    op.create_index("ix_classification_rules_owner_id", "classification_rules", ["owner_id"])
+    op.create_index("ix_classification_rules_category", "classification_rules", ["category"])
+
+
+def downgrade() -> None:
+    """Drop classification_rules table."""
+    op.drop_index("ix_classification_rules_category", "classification_rules")
+    op.drop_index("ix_classification_rules_owner_id", "classification_rules")
+    op.drop_index("ix_classification_rules_id", "classification_rules")
+    op.drop_table("classification_rules")