feat(postgres): add comprehensive PostgreSQL function support (array, network, UUID, hstore, range) (#26)

* feat(postgres): add array, network, UUID functions and fix range constructors

New function modules:
- array.py: 17 array functions (array_agg, array_append, etc.)
- network.py: 15 network functions (inet_client_addr, inet_merge, etc.)
- uuid.py: 7 UUID functions (uuid_generate_v1, uuid_generate_v4, etc.)

Fix range constructors to use sentinel pattern for bounds parameter:
- int4range, int8range, numrange, tsrange, tstzrange, daterange
- Omit bounds when using default inclusive '[]', include when explicitly specified

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

* feat(postgres): add comprehensive hstore function support

Add PostgreSQL hstore extension functions including:
- Constructors: hstore_from_record, hstore_from_key_value
- Key/Value extraction: akeys, skeys, avals, svals, each
- Conversion: hstore_to_array, hstore_to_matrix, hstore_to_json,
  hstore_to_jsonb, hstore_to_json_loose, hstore_to_jsonb_loose
- Existence: hstore_exist, hstore_defined
- Delete: hstore_delete, hstore_delete_keys, hstore_delete_pairs
- Record: hstore_populate_record
- Operators: hstore_get_value, hstore_get_values, hstore_concat,
  hstore_key_exists, hstore_all_keys_exist, hstore_any_key_exists,
  hstore_contains, hstore_contained_by, hstore_subtract_*,
  hstore_to_array_operator, hstore_to_matrix_operator,
  hstore_record_update
- Subscript: hstore_subscript_get, hstore_subscript_set

Note: Generic function names (exist, delete, defined, slice,
populate_record, record_update) are prefixed with hstore_ to
avoid confusion with unrelated functionality.

* refactor(postgres): rename hstore extraction functions with hstore_ prefix

Rename generic function names to avoid confusion:
- akeys → hstore_akeys
- skeys → hstore_skeys
- avals → hstore_avals
- svals → hstore_svals
- each → hstore_each

All hstore functions now consistently use the hstore_ prefix.

* chore: add changelog fragment for PR #26

* test(postgres): add hstore function tests for full coverage

---------

Co-authored-by: Claude Opus 4.6 <noreply@anthropic.com>

Author: vistart

changelog.d/26.added.md

@@ -0,0 +1 @@
+Added comprehensive PostgreSQL function support: array (18), network address (16), UUID (8), hstore (33), and range constructors (6).

src/rhosocial/activerecord/backend/impl/postgres/functions/__init__.py

@@ -146,6 +146,99 @@
     avg,
 )
 
+# Array functions
+from .array import (
+    array_agg,
+    array_append,
+    array_cat,
+    array_dims,
+    array_fill,
+    array_length,
+    array_lower,
+    array_ndims,
+    array_position,
+    array_positions,
+    array_prepend,
+    array_remove,
+    array_replace,
+    array_to_string,
+    array_upper,
+    unnest,
+    array_agg_distinct,
+    string_to_array,
+)
+
+# Network address functions
+from .network import (
+    inet_client_addr,
+    inet_client_port,
+    inet_server_addr,
+    inet_server_port,
+    inet_merge,
+    inet_and,
+    inet_or,
+    inetnot,
+    inet_set_mask,
+    inet_masklen,
+    inet_netmask,
+    inet_network,
+    inet_recv,
+    inet_show,
+    cidr_netmask,
+    macaddr8_set7bit,
+)
+
+# UUID functions
+from .uuid import (
+    uuid_generate_v1,
+    uuid_generate_v1mc,
+    uuid_generate_v3,
+    uuid_generate_v4,
+    uuid_generate_v5,
+    uuid_nil,
+    uuid_max,
+)
+
+# hstore functions
+from .hstore import (
+    hstore_from_record,
+    hstore_from_key_value,
+    hstore_akeys,
+    hstore_skeys,
+    hstore_avals,
+    hstore_svals,
+    hstore_each,
+    hstore_to_array,
+    hstore_to_matrix,
+    hstore_to_json,
+    hstore_to_jsonb,
+    hstore_to_json_loose,
+    hstore_to_jsonb_loose,
+    hstore_slice,
+    hstore_exist,
+    hstore_defined,
+    hstore_delete,
+    hstore_delete_keys,
+    hstore_delete_pairs,
+    hstore_populate_record,
+    hstore_get_value,
+    hstore_get_values,
+    hstore_concat,
+    hstore_key_exists,
+    hstore_all_keys_exist,
+    hstore_any_key_exists,
+    hstore_contains,
+    hstore_contained_by,
+    hstore_subtract_key,
+    hstore_subtract_keys,
+    hstore_subtract_pairs,
+    hstore_to_array_operator,
+    hstore_to_matrix_operator,
+    hstore_record_update,
+    hstore_subscript_get,
+    hstore_subscript_set,
+)
+
 
 __all__ = [
     # Range functions
@@ -247,4 +340,92 @@
     "max_",
     "min_",
     "avg",
+    # Array functions
+    "array_agg",
+    "array_append",
+    "array_cat",
+    "array_dims",
+    "array_fill",
+    "array_length",
+    "array_lower",
+    "array_ndims",
+    "array_position",
+    "array_positions",
+    "array_prepend",
+    "array_remove",
+    "array_replace",
+    "array_to_string",
+    "array_upper",
+    "unnest",
+    "array_agg_distinct",
+    "string_to_array",
+    # Network address functions
+    "inet_client_addr",
+    "inet_client_port",
+    "inet_server_addr",
+    "inet_server_port",
+    "inet_merge",
+    "inet_and",
+    "inet_or",
+    "inetnot",
+    "inet_set_mask",
+    "inet_masklen",
+    "inet_netmask",
+    "inet_network",
+    "inet_recv",
+    "inet_show",
+    "cidr_netmask",
+    "macaddr8_set7bit",
+    # UUID functions
+    "uuid_generate_v1",
+    "uuid_generate_v1mc",
+    "uuid_generate_v3",
+    "uuid_generate_v4",
+    "uuid_generate_v5",
+    "uuid_nil",
+    "uuid_max",
+    # hstore functions
+    "hstore_from_record",
+    "hstore_from_key_value",
+    "hstore_akeys",
+    "hstore_skeys",
+    "hstore_avals",
+    "hstore_svals",
+    "hstore_each",
+    "hstore_to_array",
+    "hstore_to_matrix",
+    "hstore_to_json",
+    "hstore_to_jsonb",
+    "hstore_to_json_loose",
+    "hstore_to_jsonb_loose",
+    "hstore_slice",
+    "hstore_exist",
+    "hstore_defined",
+    "hstore_delete",
+    "hstore_delete_keys",
+    "hstore_delete_pairs",
+    "hstore_populate_record",
+    "hstore_get_value",
+    "hstore_get_values",
+    "hstore_concat",
+    "hstore_key_exists",
+    "hstore_all_keys_exist",
+    "hstore_any_key_exists",
+    "hstore_contains",
+    "hstore_contained_by",
+    "hstore_subtract_key",
+    "hstore_subtract_keys",
+    "hstore_subtract_pairs",
+    "hstore_to_array_operator",
+    "hstore_to_matrix_operator",
+    "hstore_record_update",
+    "hstore_subscript_get",
+    "hstore_subscript_set",
+    # Range constructors
+    "int4range",
+    "int8range",
+    "numrange",
+    "tsrange",
+    "tstzrange",
+    "daterange",
 ]