Loosen dependency constraints to researched minimum versions

Replace Poetry caret ranges (^) and requirements.txt exact pins (==)
with flexible lower-bound constraints (>=) so patch/minor/major
updates aren't blocked. Minimum versions were verified against actual
API usage rather than just relaxing the previously pinned version:

- TM1py >=2.0.4: tm1.sessions.get_threads_for_current() (used by the
  `threads` command) was only introduced in TM1py 2.0; 2.0.4 also
  fixes an uncaught-exception-on-logout bug in TM1Service.__exit__
  that the `with TM1Service(...) as tm1:` pattern relies on.
- typer >=0.9.3: Annotated-based Option/Argument declarations (used
  throughout tm1cli) were introduced in typer 0.9.0, but 0.9.0-0.9.2
  have a bug evaluating annotations on Python 3.10 specifically,
  which is this project's minimum supported Python version.
- pyyaml >=5.4: yaml.FullLoader (used in tm1yaml.py to load process
  dumps) exists since 5.1, but 5.4 is the first release without the
  arbitrary-code-execution issue (CVE-2020-14343) relevant since
  `process load` deserializes user-supplied YAML files.

Dev-only tools (isort, pytest, pylint, pytest-mock) and transitive
packages in requirements.txt keep their previously pinned version as
the floor, since they aren't part of the published package's API
surface and don't warrant the same investigation.

Verified the mocked test suite, pylint, and the CLI itself against a
fresh install resolving to the latest available versions of every
dependency (TM1py 2.3.1, typer 0.26.8, pyyaml 6.0.3, rich 15.0.0).
poetry.lock was refreshed accordingly; it still resolves to the same
previously locked versions since Poetry keeps existing compatible
versions rather than force-upgrading.

Author: claude

poetry.lock

@@ -9,15 +9,15 @@ repository = "https://github.com/onefloid/tm1cli"
 
 [tool.poetry.dependencies]
 python = "^3.10"
-TM1py = "^2.0.4"
-typer = "^0.13.1"
-pyyaml = "^6.0.2"
+TM1py = ">=2.0.4"
+typer = ">=0.9.3"
+pyyaml = ">=5.4"
 
 [tool.poetry.group.dev.dependencies]
-isort = "^5.13.2"
-pytest = "^8.3.3"
-pylint = "^3.3.1"
-pytest-mock = "^3.14.0"
+isort = ">=5.13.2"
+pytest = ">=8.3.3"
+pylint = ">=3.3.1"
+pytest-mock = ">=3.14.0"
 
 [tool.poetry.scripts]
 tm1cli = "tm1cli.main:app"