
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Given a line $l$: $\sqrt{3}x - y - a = 0$, and a circle $C$ with the polar equation $\rho = 2\sin \theta$,
(Ⅰ) Find the Cartesian coordinate equation of circle $C$;
(Ⅱ) If circle $C$ is tangent to line $l$, find the value of the real number $a$.

Present the answer in LaTex format: \boxed{Your answer}
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