fix(st2client): fix TypeError when displaying help for actions with mixed parameter position types

[balgaly]

Summary

Fixes #5130 — st2 run pack.action -h crashes with TypeError: '<' not supported between instances of 'str' and 'int' when the action has some parameters with a numeric position attribute and others without.

Root cause

_get_parameter_sort_value returns either int(position) or str(name) depending on whether the parameter has a position attribute. Python 3 does not support < comparisons between int and str, so sorted() raises a TypeError when it tries to compare parameters of both kinds.

Fix

Replace the flat return value with a 3-tuple (tier, int_pos, name):

• Parameters with a position attribute return (0, int(position), "") -- sorted by position first.
• Parameters without a position attribute return (1, 0, name) -- sorted alphabetically after positioned ones.

Tuples are compared element-by-element. Because the first element always differs between the two groups (0 vs 1), Python never attempts to compare an int against a str.

Test

Reproducer (from the issue):

st2 run librenms.get_bgp_sessions -h
# was: ERROR: Unable to print help for action "librenms.get_bgp_sessions". '<' not supported between instances of 'str' and 'int'
# now: displays help correctly

The fix is additive -- any action whose parameters all have position attributes or all lack them continues to sort identically.