Add cterm module for cterm.py (#912)

We've had `cterm.py` at the top-level of the pyk library. This moves it
into a submodule in preparation for refactors to `KCFGExplore` to factor
out basic cterm manipulation commands from more complicated KCFG
manipulation commands.

- `cterm.py` is moved to `cterm/cterm.py`. Imports are adjusted.
- `cterm/__init__.py` is added, and setup so that almost no imports
elsewhere need to change.

---------

Co-authored-by: devops <devops@runtimeverification.com>

docs/conf.py

@@ -9,8 +9,8 @@
 project = 'pyk'
 author = 'Runtime Verification, Inc'
 copyright = '2024, Runtime Verification, Inc'
-version = '0.1.650'
-release = '0.1.650'
+version = '0.1.651'
+release = '0.1.651'
 
 # -- General configuration ---------------------------------------------------
 # https://www.sphinx-doc.org/en/master/usage/configuration.html#general-configuration

package/version

@@ -1 +1 @@
-0.1.650
+0.1.651

pyproject.toml

@@ -4,7 +4,7 @@ build-backend = "poetry.core.masonry.api"
 
 [tool.poetry]
 name = "pyk"
-version = "0.1.650"
+version = "0.1.651"
 description = ""
 authors = [
     "Runtime Verification, Inc. <contact@runtimeverification.com>",

src/pyk/cterm/__init__.py

@@ -0,0 +1 @@
+from .cterm import CSubst, CTerm, build_claim, build_rule

src/pyk/cterm.py → src/pyk/cterm/cterm.py

@@ -5,9 +5,9 @@
 from itertools import chain
 from typing import TYPE_CHECKING
 
-from .kast import Atts, KAtt, KInner
-from .kast.inner import KApply, KRewrite, KToken, KVariable, Subst, bottom_up
-from .kast.manip import (
+from ..kast import Atts, KAtt, KInner
+from ..kast.inner import KApply, KRewrite, KToken, KVariable, Subst, bottom_up
+from ..kast.manip import (
     abstract_term_safely,
     apply_existential_substitutions,
     count_vars,
@@ -19,17 +19,17 @@
     split_config_and_constraints,
     split_config_from,
 )
-from .kast.outer import KClaim, KRule
-from .prelude.k import GENERATED_TOP_CELL
-from .prelude.kbool import andBool, orBool
-from .prelude.ml import is_bottom, is_top, mlAnd, mlBottom, mlEqualsTrue, mlImplies, mlTop
-from .utils import single, unique
+from ..kast.outer import KClaim, KRule
+from ..prelude.k import GENERATED_TOP_CELL
+from ..prelude.kbool import andBool, orBool
+from ..prelude.ml import is_bottom, is_top, mlAnd, mlBottom, mlEqualsTrue, mlImplies, mlTop
+from ..utils import single, unique
 
 if TYPE_CHECKING:
     from collections.abc import Iterable, Iterator
     from typing import Any
 
-    from .kast.outer import KDefinition
+    from ..kast.outer import KDefinition
 
 
 @dataclass(frozen=True, order=True)