Add prefix to helper functions to prevent user code conflicts

[Chemaclass]

📚 Description

This PR addresses the namespace pollution issue (#538) that makes bashunit unusable for projects that define common function names like log, fail, mock, etc.

The Problem:
Bashunit previously defined generic function names at the global scope. When users have their own functions with the same names (e.g., a log() function in a logging module), conflicts occur silently, causing tests to fail or behave unexpectedly. Since bash has no concept of private methods or namespaces, any function defined by bashunit can collide with user code.

Example conflict scenario:

# User code defines:
function log() {
    echo "[INFO] message" >> /var/log/app.log
}

# bashunit previously also defined:
function log() {
    [[ "$BASHUNIT_DEV_MODE" == true ]] || return 0
    console::print "$@" >&2
}

# When running tests, whichever loads last "wins" - causing silent failures

The Solution:
All helper functions now use the bashunit:: namespace prefix, following the same convention already used internally (e.g., console::print, state::add_assertions_passed). This ensures bashunit functions never conflict with user-defined functions.

🔖 Changes

Function Renames (Breaking Changes)

All helper functions accessible to test files now require the bashunit:: prefix:

Before	After
skip	bashunit::skip
todo	bashunit::todo
fail	bashunit::fail
mock	bashunit::mock
unmock	bashunit::unmock
spy	bashunit::spy
temp_file	bashunit::temp_file
temp_dir	bashunit::temp_dir
data_set	bashunit::data_set
current_dir	bashunit::current_dir
current_filename	bashunit::current_filename
random_str	bashunit::random_str
log	bashunit::log
set_test_title	bashunit::set_test_title

What Remains Unchanged

• All assert_* functions keep their names (they already have a unique prefix)
• Lifecycle hooks (set_up, tear_down, set_up_before_script, tear_down_after_script) keep their names (these are user-defined functions, not bashunit-provided)

Files Updated

• Source files in src/ - renamed function definitions and internal calls
• Documentation in docs/ - updated all examples to use new names
• All test files updated to use the new function names
• CHANGELOG.md updated with migration guide

Migration Guide

Users upgrading to this version need to update their test files:

# Before
function test_example() {
    mock curl echo "mocked response"
    local result
    result="value"
    assert_equals "expected" "$result"
}

function test_skip_example() {
    skip "Not implemented yet"
}

# After
function test_example() {
    bashunit::mock curl echo "mocked response"
    local result
    result="value"
    assert_equals "expected" "$result"
}

function test_skip_example() {
    bashunit::skip "Not implemented yet"
}

Quick migration command:

# Run from your tests directory
sed -i "" \
    -e "s/\\bskip /bashunit::skip /g" \
    -e "s/\\btodo /bashunit::todo /g" \
    -e "s/\\bfail /bashunit::fail /g" \
    -e "s/\\bmock /bashunit::mock /g" \
    -e "s/\\bunmock /bashunit::unmock /g" \
    -e "s/\\bspy /bashunit::spy /g" \
    -e "s/\\btemp_file/bashunit::temp_file/g" \
    -e "s/\\btemp_dir/bashunit::temp_dir/g" \
    -e "s/\\bdata_set/bashunit::data_set/g" \
    -e "s/\\bcurrent_dir/bashunit::current_dir/g" \
    -e "s/\\bcurrent_filename/bashunit::current_filename/g" \
    *_test.sh

✅ To-do list

• I updated the CHANGELOG.md to reflect the new feature or fix
• I updated the documentation to reflect the changes

Fixes #538