Increase tn_priority max value to 9999999999

[simensol]

Describe your changes
I want to use the current timestamp (epoch) to sort the tree nodes by creation date, e.g., 1726814949. Although priority_max = 9999999999 in __get_node_order_str:

django-treenode/treenode/models.py

Lines 461 to 468 in 5663c5b

	def __get_node_order_str(self):
	priority_max = 9999999999
	priority_len = len(str(priority_max))
	priority_val = priority_max - min(self.tn_priority, priority_max)
	priority_key = str(priority_val).zfill(priority_len)
	alphabetical_val = slugify(str(self))
	alphabetical_key = alphabetical_val.ljust(priority_len, "z")
	alphabetical_key = alphabetical_key[0:priority_len]

the maximum value of the tn_priority field is set to MaxValueValidator(9999):

django-treenode/treenode/models.py

Lines 113 to 117 in 5663c5b

	tn_priority = models.PositiveIntegerField(
	default=0,
	validators=[MinValueValidator(0), MaxValueValidator(9999)],
	verbose_name=_("Priority"),
	)

My current workaround is to overwrite the tn_priority field in my own model:

class MyModel(TreeNodeModel):
    ...
    tn_priority = models.PositiveIntegerField(
        default=0,
        validators=[MinValueValidator(0), MaxValueValidator(9999999999)],
        verbose_name=_("Priority"),
    )

This pull request increases the maximum value for tn_priority to 9999999999, enabling the use of timestamps for sorting and aligning it with the priority_max value in __get_node_order_str.

Checklist before requesting a review

• I have performed a self-review of my code.
• I have added tests for the proposed changes.
• I have run the tests and there are not errors.

[fabiocaccamo]

@simensol thank you for this useful PR!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 90.96%. Comparing base (5663c5b) to head (95a841d).
Report is 4 commits behind head on main.

Additional details and impacted files

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  Coverage   90.96%   90.96%           
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  Files          11       11           
  Lines         697      697           
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  Hits          634      634           
  Misses         63       63           

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[fabiocaccamo]

@simensol thank you for this PR, you can upgrade to 0.22.1 version!

[simensol]

Thanks @fabiocaccamo, and I appreciate the fast response! The PR was merged before I even managed to apply the workaround to my own repository. Looking forward to using the new version!