5 satisfaction problems missing find_all_satisfying tests

[isPANN]

Problem

5 SatisfactionProblem models have test files but do not use find_all_satisfying to enumerate all feasible solutions, unlike the other 33 satisfaction models which all include such tests.

Additionally, 7 problems were missing canonical_model_example_specs registration (no auto-exported JSON for the paper), and their paper entries used hardcoded examples instead of load-model-example.

Affected models (find_all_satisfying)

Model	Test file	Issue example	Search space	Solutions
SequencingWithinIntervals	src/unit_tests/models/misc/sequencing_within_intervals.rs	#219 (5 tasks, overlapping windows)	5280	41
ShortestCommonSupersequence	src/unit_tests/models/misc/shortest_common_supersequence.rs	#412 instance 1 (3 strings, ternary, K=7)	2187	42
MultiprocessorScheduling	src/unit_tests/models/misc/multiprocessor_scheduling.rs	#212 (5 tasks, 2 processors, D=10)	32	2
FlowShopScheduling	src/unit_tests/models/misc/flow_shop_scheduling.rs	#507 (5 jobs, 3 machines, D=25)	120	99
RuralPostman	src/unit_tests/models/graph/rural_postman.rs	#248 instance 1 (hexagon, 8 edges, B=6)	6561	1

Affected models (missing canonical_model_example_specs + hardcoded paper)

Model	Category
BinPacking	misc / optimization
GraphPartitioning	graph / optimization
Knapsack	misc / optimization
MinimumFeedbackArcSet	graph / optimization
OptimalLinearArrangement	graph / satisfaction
SubgraphIsomorphism	graph / satisfaction
SubsetSum	misc / satisfaction

Changes made

1. Added find_all_satisfying + empty tests for all 5 satisfaction models, using issue examples with exact solution counts verified by brute force
2. Updated canonical examples for SequencingWithinIntervals ([Model] SequencingWithinIntervals #219) and ShortestCommonSupersequence ([Model] ShortestCommonSupersequence #412) to use more natural instances matching their issues
3. Registered canonical_model_example_specs for all 7 missing models (total: 70/70 problems now registered)
4. Converted all 7 paper entries from hardcoded to data-driven (load-model-example)
5. Made FlowShopScheduling and RuralPostman paper entries fully data-driven with auto-computed Gantt charts / graph figures