Some functions have an argument named "seed_type" in which it was annoying to call the seed_type() fn.
(especially for functions inside the same module)
pyinstaller tries to import electrum and its different submodules at build-time
during the "Analysis" phase. sys._GUI_QT_VERSION was not getting set there,
and the resulting exception was blocking pyinstaller from discovering that
gui/common_qt is being used.
at runtime:
```
$ ./dist/Electrum.app/Contents/MacOS/run_electrum
1.53 | E | daemon.Daemon | GUI raised exception: Exception('Error loading trustedcoin plugin: ModuleNotFoundError("No module named \'electrum.gui.common_qt\'")'). shutting down.
1.53 | E | __main__ | daemon.run_gui errored
Traceback (most recent call last):
File "electrum/plugin.py", line 135, in load_plugin
spec.loader.exec_module(module)
File "<frozen importlib._bootstrap_external>", line 883, in exec_module
File "<frozen importlib._bootstrap>", line 241, in _call_with_frames_removed
File "/Users/vagrant/electrum/dist/Electrum.app/Contents/MacOS/electrum/plugins/trustedcoin/qt.py", line 51, in <module>
from .common_qt import TrustedcoinPluginQObject
File "/Users/vagrant/electrum/dist/Electrum.app/Contents/MacOS/electrum/plugins/trustedcoin/common_qt.py", line 16, in <module>
from electrum.gui.common_qt.plugins import PluginQObject
ModuleNotFoundError: No module named 'electrum.gui.common_qt'
The above exception was the direct cause of the following exception:
Traceback (most recent call last):
File "run_electrum", line 456, in handle_cmd
d.run_gui()
File "electrum/daemon.py", line 617, in run_gui
self.gui_object = gui.ElectrumGui(config=self.config, daemon=self, plugins=self._plugins)
File "electrum/util.py", line 473, in do_profile
o = func(*args, **kw_args)
File "electrum/gui/qt/__init__.py", line 153, in __init__
self.plugins.load_plugin('trustedcoin')
File "electrum/plugin.py", line 138, in load_plugin
raise Exception(f"Error loading {name} plugin: {repr(e)}") from e
Exception: Error loading trustedcoin plugin: ModuleNotFoundError("No module named 'electrum.gui.common_qt'")
```
A new config API is introduced, and ~all of the codebase is adapted to it.
The old API is kept but mainly only for dynamic usage where its extra flexibility is needed.
Using examples, the old config API looked this:
```
>>> config.get("request_expiry", 86400)
604800
>>> config.set_key("request_expiry", 86400)
>>>
```
The new config API instead:
```
>>> config.WALLET_PAYREQ_EXPIRY_SECONDS
604800
>>> config.WALLET_PAYREQ_EXPIRY_SECONDS = 86400
>>>
```
The old API operated on arbitrary string keys, the new one uses
a static ~enum-like list of variables.
With the new API:
- there is a single centralised list of config variables, as opposed to
these being scattered all over
- no more duplication of default values (in the getters)
- there is now some (minimal for now) type-validation/conversion for
the config values
closes https://github.com/spesmilo/electrum/pull/5640
closes https://github.com/spesmilo/electrum/pull/5649
Note: there is yet a third API added here, for certain niche/abstract use-cases,
where we need a reference to the config variable itself.
It should only be used when needed:
```
>>> var = config.cv.WALLET_PAYREQ_EXPIRY_SECONDS
>>> var
<ConfigVarWithConfig key='request_expiry'>
>>> var.get()
604800
>>> var.set(3600)
>>> var.get_default_value()
86400
>>> var.is_set()
True
>>> var.is_modifiable()
True
```
