refactor: move to_rao/from_rao out of CLI helpers (#171)

[Rene0422]

Summary

• Move to_rao / from_rao from allways/cli/swap_commands/helpers.py to allways/utils/misc.py — these are unit conversions, not CLI concerns.
• Drop the now-unused TAO_TO_RAO import from helpers.py.
• Update imports in all 8 CLI modules that used these helpers: status.py, collateral.py, view.py, miner_commands.py, swap.py, quote.py, admin.py, claim.py.
• No backwards-compat re-export — direct move, callers updated in the same change.

Closes #171.

Test plan

• ruff check clean on changed files
• Full test suite: 470 passed
• Smoke import of every touched CLI module + to_rao(1.5) == 1_500_000_000 / from_rao(1_500_000_000) == 1.5
• Verified helpers module no longer exports to_rao / from_rao

[Rene0422]

@LandynDev , please review this issue.