[jeromeyyy]

Fixes #3953.

When entries is passed through the CLI, e.g.

cci task run add_picklist_entries -o picklists Account.Status__c -o entries '[{"fullName": "TestValue", "label": "Test Value"}]'

the option arrives as a JSON string, while AddPicklistEntries expects a list of dicts. The fullName check then iterates over the string's characters and always raises The 'fullName' key is required on all picklist values., exactly as reported in #3953. The sibling task add_standard_value_set_entries (AddValueSetEntries) has the same gap: it consumes entries without any parsing, so a CLI-provided JSON string fails there too.

Change

• New process_list_of_dicts_arg helper in cumulusci/core/utils.py, next to process_list_arg / process_bool_arg: returns an existing list of dicts unchanged, parses a JSON string, and raises TaskOptionsError for invalid JSON or a value that is not a list of objects.
• AddPicklistEntries._init_options and AddValueSetEntries._init_options normalize entries through it before the existing validation, so cumulusci.yml usage (already a list of dicts) is unchanged.

Tests

New regression tests in test_picklists.py and test_value_sets.py cover entries given as a JSON string (parsed and validated) and invalid JSON (raises TaskOptionsError). The picklists test reproduces the exact error from #3953 against the original code; all four tests fail before the fix and pass after.

Full suite: 3283 passed, 5 failed - all 5 failures verified to pre-exist on a clean tree (4 OAuth client tests and test_bad_entry_point; they fail identically without this change and are unrelated to it).

[salesforce-cla]

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